TC Ord. No. 2010-18 Adopting Local Designation of Noxious WeedsTOWN OF AVON, COLORADO
ORDINANCE 10 -18
SERIES OF 2010
AN ORDINANCE ADOPTING LOCAL DESIGNATION OF NOXIOUS WEEDS
WHEREAS, the Town of Avon ( "Town ") is a home rule authority municipal corporation
and body politic organized under the laws of the State of Colorado and possessing the maximum
powers, authority and privileges to which it is entitled under Colorado law; and
WHEREAS, the Town Council is authorized to declare nuisances, establish fines and
penalties, and require abatement of public nuisances pursuant to its home rule authority and
pursuant to Colorado Revised Statute §31- 15- 401(1)(c); and
WHEREAS, the Town Council is authorized to provide for the removal of weeds pursuant
to Colorado Revised Statutes §31- 15- 401(1)(d); and
WHEREAS, the Town Council is authorized to implement and enforce the Colorado
Noxious Weed Act, C.R.S. §35 -5.5 -101 et. seq.; and
WHEREAS, the Town Council adopted Ordinance No. 10 -06 An Ordinance Enacting
Noxious Weed Controls on April 27, 2010; and
WHEREAS, C.R.S. §35 -5.5- 108(3) provides that the governing body of a municipality may
declare additional noxious weeds after a public hearing with thirty days notice to the public; and
WHEREAS, notice of the local designation of noxious weeds was posted on August 27,
2010 in accordance with the requirements in the Home Rule Charter of the Town of Avon; and
WHEREAS, the Town Council conducted public hearing on this Ordinance on September
28, 2010; October 12, 2010; and October 26, 2010; and
WHEREAS, it is the Town Council's opinion that the health, safety and welfare of the
citizens of the Town of Avon would be enhanced and promoted by the adoption of this
ordinance; and
WHEREAS, approval of this Ordinance on first reading is intended only to confirm that the
Town Council desires to comply the requirements of the Avon Home Rule Charter by setting a
public hearing in order to provide the public an opportunity to present testimony and evidence
regarding the application and that approval of this Ordinance on first reading does not constitute
a representation that the Town Council, or any member of the Town Council, supports, approves,
rejects, or denies this ordinance;
NOW THEREFORE, BE IT ORDAINED BY THE TOWN COUNCIL OF THE
TOWN OF AVON, COLORADO, the following:
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 1 of 3
V2 10.26.10
Section 1. Recitals Incorporated. The above and foregoing recitals are incorporated herein by
reference and adopted as findings and determinations of the Town Council.
Section 2. Adoption of Local Designation of Noxious Weeds. The Town Council, as the
governing body of the Town of Avon, hereby adopts the local designation of noxious weeds as
such weeds are set forth in the Town of Avon Noxious Weed Management Plan, dated August
27, 2010, attached hereto as Exhibit A.
Section 3. Noxious Weed Management Plan Adopted. The Town of Avon Noxious Weed
Management Plan, dated August 27, 2010, attached hereto as Exhibit A is hereby adopted in its
entirety.
Section 4. Codification Amendments. The codifier of the Town's Municipal Code, Colorado
Code Publishing, is hereby authorized to make such numerical and formatting changes as may be
necessary to incorporate the provisions of this Ordinance within the Avon Municipal Code. The
Town Clerk is authorized to correct, or approve the correction by the codifier, of any
typographical error in the enacted regulations, provided that such correction shall not
substantively change any provision of the regulations adopted in this Ordinance. Such
corrections may include spelling, reference, citation, enumeration, and grammatical errors.
Section 5. Severability. If any provision of this Ordinance, or the application of such provision
to any person or circumstance, is for any reason held to be invalid, such invalidity shall not affect
other provisions or applications of this Ordinance which can be given effect without the invalid
provision or application, and to this end the provisions of this Ordinance are declared to be
severable. The Town Council hereby declares that it would have passed this Ordinance and each
provision thereof, even though any one of the provisions might be declared unconstitutional or
invalid. As used in this Section, the term "provision" means and includes any part, division,
subdivision, section, subsection, sentence, clause or phrase; the term "application" means and
includes an application of,an ordinance or any part thereof, whether considered or construed
alone or together with another ordinance or ordinances, or part thereof, of the Town.
Section 6. Effective Date. This Ordinance shall take effect seven days after public notice
following final passage in accordance with Section 6.4 of the Avon Home Rule Charter.
Section 7. Safety Clause. The Town Council hereby finds, determines and declares that this
Ordinance is promulgated under the general police power of the Town of Avon, that it is
promulgated for the health, safety and welfare of the public, and that this Ordinance is necessary
for the preservation of health and safety and for the protection of public convenience and
welfare. The Town Council further determines that the Ordinance bears a rational relation to the
proper legislative object sought to be obtained.
Section 8. No Existing Violation Affected. Nothing in this Ordinance shall be construed to
release, extinguish, alter, modify, or change in whole or in part any penalty, liability or right or
affect any audit, suit, or proceeding pending in any court, or any rights acquired, or liability
incurred, or any cause or causes of action acquired or existing which may have been incurred or
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 2 of 3
V2 10.26.10
obtained under any ordinance or provision hereby repealed or amended by this Ordinance. Any
such ordinance or provision thereof so amended, repealed, or superseded by this Ordinance shall
be treated and held as remaining in force for the purpose of sustaining any and all proper actions,
suits, proceedings and prosecutions, for the enforcement of such penalty, liability, or right, and
for the purpose of sustaining any judgment, decree or order which can or may be rendered,
entered, or made in such actions, suits or proceedings, or prosecutions imposing, inflicting, or
declaring such penalty or liability or enforcing such right, and shall be treated and held as
remaining in force for the purpose of sustaining any and all proceedings, actions, hearings, and
appeals pending before any court or administrative tribunal.
Section 9. Publication by Posting. The Town Clerk is ordered to publish this Ordinance by
posting notice of adoption of this Ordinance on final reading by title in at least three public
places within the Town and posting at the office of the Town Clerk, which notice shall contain a
statement that a copy of the ordinance in full is available for public inspection in the office of the
Town Clerk during normal business hours.
INTRODUCED, APPROVED, PASSED ON FIRST READING, ORDERED POSTED
AND REFERRED TO PUBLIC HEARING and setting such public hearing for October 12,
2010 at the Council Chambers of the Avon Munici uilding, located at One Lake Street, Avon,
Colorado, on September 28, 2010.
-pWN OFq�0 Ronald C. Wolfe, Mayor
Published by sti 1 at least tl
Clerk at least v�nlld s4i�r to
ATTEST: °iORAn6
mil's'( .3 tyl
at ""Kenny, Tdwn
public places in Town and posting at the office of the Town
I action by the Town Council.
APP - OOVVED ASIO FORM:
Eric Heil, Town Attorney
INTRODUCED, FINT �,Y APPROVED, AND P SED ON SECOND READING, AND
ORDERED PUBLISHED BY POSTING on.Oc e— fr, 2010.
ria Sipes, Mayor Pro -Tem
Published by posting by title in at least three public places in Town and posting by title at the
office of the Town Clerk. N OFq�
o�
T:
Mc enny, To k
o °�o�AOO.
Ord. No. 10 -18 Adopting Loc ation of Noxious Weeds
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V2 10.26.10
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
TOWN OF AVON
NOXIOUS WEED MANAGEMENT PLAN
ADOPTED BY THE TOWN COUNCIL ACTING AS
THE LOCAL WEED ADVISORY BOARD
ON OCTOBER 26, 2010
The Town of Avon in accordance with "Colorado Noxious Weed Act ", C.R.S. §35 -5.5 -101 et seq.
hereby designates the following plants as Noxious Weeds:
Management Method #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Common Name:
Leafy Spurge
Russian Knapweed
Diffuse Knapweed
Spotted Knapweed
Canada Thistle
Musk Thistle
Plumeless Thistle
Scotch Thistle
Houndstongue
Whitetop /Hoary Cress
Yellow Toadflax
Oxeye Daisy
Dalmatian Toadflax
Common Tansy
Scentless Chamomile
Salt Cedar
Yellow Sweet Clover
Black henbane
Bull Thistle
Chinese clematis
Eurasian watermilfoil
Perennial pepperweed
Russian -olive
24 Spurred anoda
25 Sulfur cinquefoil
26 Venice mallow
Scientific Name:
Euphorbia esula
Acroptilon repens
Centaurea diffusa
Centaurea maculosa
Cirsium arvense
Carduus nutans
Carduus acanthoides
Onopordum acanthium
Cynoglossum officinale
Cardaria draba
Linaria vulgaris
Chrysanthemum leucanthemum
Linaria dalmatica
Tanacetum vulgare
Matricaria perforate
Tamarix chinensis
Melilotus offrcinalis
Hyoscyamus niger
Cirsium vulgare
Clematis orientalis
Myriophyllum spicatum
Lepidium latifolium
Elaeagnus angusifolia
Anoda cristata
Potentilla recta
Hibiscus trionum
The purpose of this Noxious Weed Management Plan is to adopt a list of noxious weeds for the
Town of Avon. The basis for this list is set forth in the "Colorado Noxious Weed Act" C.R.S. §35-
5.5 -101 et seq. Weeds which commonly occur in Avon and which are listed on the state's A, B, and
C list at the time of adoption are identified above. In addition, yellow sweet clover (Melilotus
offrcinalis) has been identified as noxious by the Town of Avon. Although this plant is not
Town of Avon: Noxious Weed Management Plan
Page 1 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
currently listed on the state's list, it is identified as noxious by the town and included herein because
it is very invasive, detrimental to cattle, has been found to be problematic in Avon, and is expected
to be added to the state's noxious weed list.2
It is expressly understood in this Plan that the above - referenced list shall be inclusive of all "List A"
species of noxious weeds to the extent they are found within the Town of Avon and identified for
mandatory eradication by the State of Colorado. It is also expressly understood that any and all
"List B" species of noxious weeds not currently listed above, but later found within the Town of
Avon and identified by the state for mandatory eradication pursuant to state regulation 8 CCR 1203-
19, shall be incorporated into this plan and that no amendment hereto shall be necessary prior to
taking enforcement action for the eradication of said species.
The Town of Avon may annually review and update this list of noxious weeds pursuant to state
statute, or sooner if necessary.
Introduction
The noxious weeds that have currently invaded our community have become a threat to the
economic and environmental value of land in the Town of Avon. These weeds are not
indigenous to this county and have no natural predators or diseases to keep them in check.
They are rapidly displacing desirable vegetation causing a loss of productive wildlife
grazing and recreational resources. An integrated noxious weed management plan must
include best practice strategies along with the Federal, State of Colorado, Town of Avon and
Private land owners, working together to meet the challenges we now face in our state.
II. Goals of this plan
• Adopting and implementing the Colorado Noxious Weed Act as they apply to the Town
of Avon. The Town of Avon Noxious Weed Regulations as it pertains to noxious weeds
will automatically update along with all future revisions and amendments to the
Colorado Noxious Weed Act.
• Education of the public and private landowners concerning weed management issues
facing our community.
• Work with the Federal, State, County, and private landowners to implement "Best
Management Practices. "
• Identify, inventory and map out noxious weeds currently in our community and use as a
means to monitor our effectiveness and as a tool for future work plans.
III. Weed Management Methods
The Colorado Noxious Weed Act provides that integrated methods must be utilized in the
management of weeds. Integrated methods include but are not limited to: Cultural,
2 This species is listed as invasive in 26 states including Colorado, Arizona, Texas, Wyoming, and Utah. See
U.S. Forest Service. Weed of the Week: Yellow Sweetclover. Accessed February 2009:
http: / /www.na.fs.fed.us /fhp /invasive plants /weeds /vellow sweetclover.pdf
Whitson, T.D. (ed.) et al. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative
Extension Services, University of Wyoming. Laramie, Wyoming.
United States Department of Agriculture, Accessed online on April 8, 2010 at
hftp://plants.usda.gov/iava/profile?svmbol=MEOF.
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
Chemical, Biological and Mechanical management. For proper control of a particular weed
species, it may be necessary to utilize more than one method. The following general
comments regard control methodology apply to all listed or otherwise identified noxious
weeds, unless otherwise specifically excluded in the detailed management plan listed below
for a particular plant species:
• Cultural — those methodologies or practices conducted to favor the growth of
desirable plants over undesirable plants. Including but not limited to: maintaining an
optimum fertility and plant moisture status in an area, and planting species most
suited to an area. (e.g., Grazing, Revegetation for wildlife)
• Erosion Control — Healthy plant revegetation of all disturbed sites with acceptable
grasses, trees, and other plantings, with a 2 year warranty and extensive weed control
during the re- growth period.
• Chemical — the use of herbicides or plant growth regulators to disrupt the growth of
undesirable plants. (e.g., Herbicides)
• Biological — the use of organisms to disrupt the growth of undesirable plants. (e.g.,
insects, bacteria, pathogens, goats)
• Mechanical — practices that physically disrupt plant growth including but not limited
to: tilling, mowing, burning, cutting, mulching, hand pulling, and hoeing. Tilling,
mowing, mulching, and hoeing are generally only effective if done to plants prior to
the flowering stage. After this stage the seeds have formed and these plants must be
completely removed from the property by cutting or hand - pulling as part of the
mitigation effort Cut plants which include buds, flowers, or seed pods should be
placed in clear plastic bags, the bags labeled "noxious weeds ", and landfill disposed.
Landfill disposal should be done through a licensed landscape maintenance
contractor or by direct deposit in the landfill. Unless otherwise recommended below,
no removed weed material which includes buds, flowers, or seed pods should be
burned, composted, or heaped, or otherwise left exposed.
Note that personal protective equipment (PPE) should be worn when conducting weed
mitigation. This may include gloves, long sleeve shorts, full length pants, safety boots, and
safety glasses. Mitigation work should be done carefully because some of the weeds and
herbicides can cause eye and /or skin irritation.
IV. Managed Species Information
1. Leafy spurge - (Euphorbia esula) a perennial that spreads by seed and creeping rootstocks.
An extensive root system with vast nutrient reserves makes this plant extremely difficult to
control. Management Methods:
a) Cultural: seeding perennial grasses can be an effective management tool. Early emerging
plant species that utilize early season moisture such as smooth brone (Bromus inermis)
or crested wheat grass have reduced leafy spurge density and limited the spread and
establishment of new infestations. Alfalfa can also be a good competitor with leafy
spurge.
b) Chemical: Contact a licensed commercial applicator for specific recommendations for
herbicide use.
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
c) Biological: grazing with sheep or goats can stress leafy spurge making it more
susceptible to other control methods. Apthona flava and Apthona nigriscutis are two
species of flea beetles that have been introduced to attack leafy spurge. Adults feed on
foliage during summer and lay eggs at the base of spurge plants. The larvae tunnel the
soil and mine the roots as well as the fine root hairs. These insects along will not control
leafy spurge but they can weaken the plant making it more susceptible to herbicide
treatments or other control methods.
d) Mechanical: mechanical methods have not been proven to be an effective management
tool on this plant.
Comments: A complex of insects, grazing, plant disease and chemical methods will be
necessary to stress the plant sufficiently to attain acceptable control.
2. Russian Knapweed - (Acroptilon repens) A creeping perennial weed which once
established, becomes extremely difficult to control. In heavy infestations few plants can
grow in competition. Management Methods:
a) Cultural: dry range seeded with Crested wheatgrass can cause stress in knapweed by
using up moisture for spring growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: a leaf & stem gall- forming nematode (Subanguina peridus) has been released
in the U.S. This nematode had shown limited success in controlling Russian knapweed
d) Mechanical: due to the extensive energy reserves in the root system, removal of top
growth alone will not provide adequate control of Russian knapweed. In fact recent
studies have shown that mowing increases Russian knapweed density and stimulates
growth.
3. Diffuse Knapweed - (Centaurea diffusa) is a biennial or short lived perennial which has
become one of the most damaging rangeland weeds in the Northwest inter - mountain area.
Management Methods:
a) Cultural: Seeding of Crested wheatgrass can inhibit the spread of diffuse knapweed in
dry climates
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies (Uphora affins and Uphora quadrifaciata)
attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
4. Spotted Knapweed - (Centaurea maculosa) is a biennial or short lived perennial that
greatly reduces the range's carrying capacity for both livestock and wildlife. Management
Methods:
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a) Cultural: Good grazing management is one of the best defenses against the spread of
knapweeds on the range and pasture lands. Proper stocking rates, good livestock
distribution and correct timing and deferment of grazing are essential to the maintenance
of a healthy range or pasture environment.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies ( Uphora affins and Uphora quadrifaciata)
attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
5. Canada Thistle — (Cirsium arvense ) A perennial weed with an extensive root system,
Canada Thistle reproduces both by seed and by vegetation buds on the roots. This requires a
much more extensive management plan than the biennial thistles. Management Methods:
a) Cultural: Cultivation may increase the number of plants by spreading the roots to new
areas where they may become established. Competitive crops, especially alfalfa and
forage grasses may be used to control Canada thistle infestations. Choose aggressive
grass with early season vigor to plant in areas where Canada thistle is present.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Ceutorhynchus litura is a stem weevil whose larvae mine tissues of the leaf,
root crown and root. Outward signs of damage by this larvae are not readily apparent but
secondary damage is caused by other organisms which enter the plants through exit
holes made by the larvae. Urophora cardui is a stem gall fly whose larvae cause galls to
form on the stem of Canada thistle plants. The galls reduce the plant's vigor making it
less able to compete with other plants or to resist pathogens or attacks by other insects. It
is essential that both of these insects be combined with other methods of control for
adequate management of Canada thistle.
d) Mechanical: Mowing can be an effective tool when combined with herbicide treatment.
Mowing alone is not effective unless conducted at two week intervals over several
growing seasons. Mowing should always be combined with cultural and chemical
control.
6. Musk Thistle — (Carduus nutans) is a biennial weed. Biennial weeds are best controlled in
their first year of growth. Very commonly found noxious weed in Eagle County.
Management Methods:
a) Cultural: The best way to prevent or reduce the amount of biennial thistle is to manage
areas that are susceptible to invasion
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
c) Biological: Rhinocyllus conicus is a flower head weevil which is widely distributed in
Eagle County. This weevil consumes most of the seeds in the terminal flower heads, but
has no effect on buds which form later in the season. The conicus weevil can be an
effective control method only if it is combined with chemical mechanical controls.
Trichosirocalus horridus is a crown weevil which feeds on the growing tip of the thistle
rosette. This weevil has been released on numerous occasions in Eagle County but has
not yet become established. Due to the very nature of the predator prey cycle the bio
control listed above will not completely eliminate the thistle.
d) Mechanical: Since these thistles are biennials and do not resprout, they are easily killed
by tillage or any method that severs the taproot below the crown of the plant. If dug or
cut after seed heads have formed the plants should be burned or otherwise destroyed so
the seeds will not mature. Mowing is effective only if done when flowers first open.
Comments: A second mowing may be necessary because the plants may recover and
produce viable seed later in the growing season.
7. Plumeless Thistle — (Carduus acanthoides). See description and management method for
the Musk Thistle ( #6 above).
8. Scotch Thistle — (Onopordum acanthium). See description and management method for the
Musk Thistle ( #6 above)
9. Houndstongue — (Cynoglossum officinale) is a biennial weed which is toxic to horses and
cattle. The seed is contained in pods, which are covered with barbs enabling them to stick to
clothing or animal hair, and thus readily transported. Management Methods:
a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No biological controls are available at this time.
d) Mechanical: Severing the taproot below the crown will control Houndstongue. After
cutting, the plants should be burned or removed if they are in bloom to prevent seed
formation.
10. Hoary Cress Whitetop — (Cardaria draba ) is a perennial plant, which is very competitive
with native vegetation. Its early seeding habits make it difficult to effect control in a timely
manner. Management Methods:
a) Cultural: The effectiveness of mowing or cultivation will be increased if perennial
grasses or alfalfa are seeded as competitor species. Promote healthy grass in rangeland
or pastures by using proper irrigation and fertilization techniques.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No insects are known to be effective for controlling this weed.
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
d) Mechanical: No scientific data is available on mechanical control for this species.
Mowing just prior to seed set may reduce overall seed production, but must repeated
several times during the growing season.
11. Yellow Toadflax - (Linaria vulgaris) This deep- rooted perennial plant is an aggressive
invader of rangeland, pasture and waste areas. Once established on a site it is one of the
most difficult noxious weeds to control. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the arnount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a
year for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
12. Dalmation Toadflax — (Linaria dalmatica) An introduced perennial with a creeping root
system. This plant may suppress desirable grasses even in well managed rangeland or
pastures. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the amount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a
year for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
13. Oxeye Daisy — (Chrysanthemum leucanthemum) A member of the sunflower family is an
erect perennial plant with white ray and yellow disk flowers which bloom from June through
August. A native of Eurasia, this aggressive plant has escaped cultivation and become a
troublesome weed in the Intermountain West.
Management Methods:
Town of Avon: Noxious Weed Management Plan
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8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known
d) Mechanical: Hand pulling or digging before seed head production can used to effectively
control small infestations. However, for this method to be successful it is important to
remove as much of the underground part as possible.
14. Scentless Chamomile — (Marticaria perforata) An escaped ornamental plant, this annual
has become widely established in the eastern part of Eagle County and is a threat to native
plant communities. Management methods:
a) Cultural: Learn to identify the plant and physically remove them when they first appear.
Seed competitive cool season grasses that out compete this plant at its early stage of
growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No known biological controls
d) Mechanical: Since it is an annual plant, chamomile can be controlled by hand pulling,
cultivation, or any type of physical disturbance.
15. Common Tansy - (Tanacetum vulgare) An escaped ornamental, is a perennial plant, from 1
Meet to 6 feet tall with showy button -like flowers. Tansy is a member of the sunflower
family and has become widely established on the western slope of Colorado. Flowering
typically occurs from July to September. Tansy reproduces by both seed and creeping
rootstock. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known
d) Mechanical: can be mowed before flowering and seed set to eliminate seed production.
This method may have to be repeated to eliminate regrowth from the rootstock.
16. Salt Cedar (Tamarix chinensis) is a evergreen shrub or small tree which grows near water
and hydric soils and reaches a height of 5 to 20 feet tall. The leaves are small, scale -like and
bluish -green in color. Tiny pink to white colored flowers have five petals and grow on
slender racemes. Salt Cedar reproduces by seed. This is an aggressive plant that
outcompetes native vegetation and consumes a lot of water. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
Town of Avon: Noxious Weed Management Plan
Page 8 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Salt Cedar Leaf Beetle (Diorhabda elongate) larvae and adults feed on
foliage and can cause plant death if defoliation is consistent. This beetle is commercially
available for distribution.
d) Mechanical: A bulldozer, chainsaw, or prescribed fire can be used in conjuction with
follow -up herbicide treatment for returning sprouts.
17. Yellow Sweet Clover (Melilotus officinalis) is an annual or biennial legume which grows
from 2 to 6 feet tall. It has small yellow to white flowers in a multiflowered terminal and
along auxillary racemes, serrated trifoliate leaves, somewhat resembles alfalfa. It is not
native to Colorado and appears on disturbed sites. It is a drought - tolerant plant. Although
useful for honey producers, it causes bloat in cattle and anticoagulation of blood. The plant
degrades native grasslands and reduces biodiversity by competing for nutrients and by
covering and shading native sun - loving plant species. It reproduces by seed, producing as
many as 100,000 seeds per plant; seeds may remain viable for up to 20 years. Management
Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
C) Biological: Sitona cylindricollis, the sweetclover weevil, may severely damage the plant.
Adults of the insect feed on the foliage and larvae feed on the roots of the plant. A
sweetclover root borer, Walshia miscecolrella, is a native insect that may damage
sweetclover plants on rare occasions. An ash -gray blister beetle, Epicauta fabricii, a
striped blister beetle, Epicauta vittata, and a margined blister beetle, Epicauta pestifera,
have also been found feeding on the plant. Yellow sweetclover is palatable by livestock
- within the risks mentioned above - and plant infestations may be reduced if heavily
grazed.
d) Mechanical: Hand pull early and when the soil is moist. Completely remove all plants
containing seeds. Burning has had variable results, including increasing germination,
and is therefore not recommended.
18. Black henbane (Hyoscyamus niger) was introduced from Europe as an ornamental and
medicinal herb; it is now found across on the western slope of Colorado. A mature plant
reaches 1 to 3 feet in height with foliage that has a fowl odor. Fruits are approximately 1
inch long with 5 lobes. It is often found in disturbed open spaces, roadsides, fields, waste
places and abandoned gardens. It grows in most soil types but likes sandy or well drained
loam soils. The seed viability or longevity is considered to be 1 to 5 years. All parts of
Black henbane are poisonous to both livestock and humans when ingested. The plant is a
strong competitor for moisture and nutrients and produces a persistent litter effecting
germination and growth of native plants. Management Methods:
Town of Avon: Noxious Weed Management Plan
Page 9 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a) Cultural: Cultural controls are possible in theory, but are very time consuming and
expensive. Complete removal of any seedlings or newly established plants by continual
hand pulling is also possible.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
d) Mechanical: Hand pull or dig from moist soil, so the entire tap root system can be
removed. Tillage will control henbane, but is usually not recommended due to the land it
occupies: rangeland, roadsides and pastures. Be sure to bag specimens carefully if
removed during or after flowering.
Comments: A preventable measure is to guard against disturbance and overgrazing.
Controlling plants in the spring or early summer prior to seed production is most effective,
follow -up treatments are recommended to pick up missed or late bolting plants.
19. Bull Thistle (Cirsium vulgare) is a biennial forb that was accidently introduced to North
America as a seed contaminant. In Colorado, Bull thistles are the only species that are
prickly hairy on the top and are cottony -hairy on the undersides of the leaves. Mature plants
can produce up to 4,000 seeds per plant. Commonly seen in areas such as pastures,
overgrazed rangeland, roadsides, and logged areas. It is not especially shade tolerant.
Bull thistle is an aggressive weed and is often a transient species, appearing in recent clear
cuts or disturbed areas and becoming a dominant species for several years. It has been
reported to cause hay fever in some individuals and is often confused with musk thistle.
Bull thistle infestations have been reported to occur in nearly all Colorado counties west of
the continental divide, in the Upper Arkansas Watershed, and in pockets on the plains.
Heavy infestations can reduce livestock forage. The presence of bull thistle in hay decreases
the forage value and lowers the market price. Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
Contact your local Natural Resources Conservation Service for seed mix
recommendations. Maintain healthy pastures and prevent bare spots caused by
overgrazing.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Urophora stylata, a fly predator, is used to help control this thistle. The
female fly lays eggs in the seed head of the thistle. The maggot then consumes the seed
in the flower. This species has overwintered in Colorado but the limited numbers will
not allow for general redistribution. For more information, contact the Palisade Insectary
of the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Because biennial thistles do not reproduce from their roots, any mechanical
or physical method that severs the root below the soil surface will kill the weed. It is
necessary to revegetate the site with desirable plants. Tillage, hoeing, or even hand-
Town of Avon: Noxious Weed Management Plan
Page 10 of 15
8/2712010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
pulling should be successful (not on rangeland), providing it is done before the
reproductive growth stages.
Comments: The key to effective control is maintaining healthy pastures and rangeland,
guarding against disturbance or overuse, and to limit seed production by collecting and
destroying plants with seeds. Chemical control is most effective when plants are in rosette
stage, spring or early fall. Mechanical controls can be used to eliminate small patches or
plants in a later growth stages.
20. Chinese clematis (Clematis orientalis) is an herbaceous to woody vined perennial which
can climb up to 12 feet. It is native to Eurasia. It has solitary flowers with four yellow
sepals (flowering from August to September) which produces numerous feathery, long -
tailed fruits which are conspicuous all winter. This plant prefers roadsides, riparian
corridors, and rocky slopes although it is sometimes found in open woods. This species can
cause death to young trees and brush. It outcompetes native shrubby and herbaceous species.
Plants will completely cover rock walls, trees, bushes and fences. The juice of freshly
crushed leaves and stems have blister causing agents. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
d) Mechanical: Handpull or dig when soil is moist. Make certain to pull all the roots. Bag
specimens carefully so as to not scatter seeds if flowering.
21. Eurasian watermilfoil (Myriophyllum spicatum) is an aquatic weed with feathery
underwater foliage that is native to Northern Europe and Asia. Eurasian watermilfoil spreads
most commonly by stem fragmentation , runners, and from free floating plants which
eventually root. It can also spread by seed. The plant is typically submersed with stems to 4
m long. Habitats for Eurasian watermilfoil include: ponds, lakes, rivers, streams, canals, and
ditches. Usually the plant inhabits slow moving water areas but can infest fast moving
water, such as streams and rivers. Eurasian watermilfoil is very invasive. The plant forms
very dense mats of vegetation on the surface of the water. Mats interfere with recreational
activities (e.g. swimming, fishing, skiing, boating, etc.), create mosquito habitat, reduce
native vegetation, and clog intake structures in power generation, irrigation systems, and
potable water intakes. Management Methods:
a) Cultural: Prevention of Eurasian watermilfoil is the best cultural control. Other methods
of cultural controls are possible in theory, but are very time consuming and expensive.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: There is biological control available for Eurasian watermilfoil, but it is not
yet approved for use in Colorado. For more information, contact the Palisade Insectary
of the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Hand pulling, raking, harvesting are effective at reducing current
abundance of plants and is useful to clear channels or maintain access. However; it is not
Town of Avon: Noxious Weed Management Plan
Pagel 1 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a very good long term control and is very expensive, labor intensive, and several
removals are needed each year.
Comments: The key to effective control is typically prevention of uncontrolled
monocultures . Chemical and mechanical controls are well developed, but provide short to
medium -term control.
22. Perennial pepperweed (Lepidium latifolium) is an extremely invasive perennial forb
introduced from Europe and Asia as a containment in sugar beet seed. Pepperweed
reproduces both by seed and vegetatively by roots and shoots. Pepperweed has tiny white
spoon- shaped petals on the flowers. It readily invades disturbed and bareground areas.
Pepperweed is a serious threat because it alters ecosystems by acting as a "salt pump"
absorbing salts from deep in the soil. The plant then excretes the salt through the leaves and
deposits it on the surface soil. Since most desirable plants do not tolerate high saline
concentrated soils, the entire plant composition and diversity of the area changes. Large
monocultures and dense litter layers prevent native plants from regenerating. Pepperweed
displaces native plants and wildlife habitats, reduces food quality for wildlife and reduces
agricultural and pasture production. Management Methods:
a) Cultural: Prolonged spring flooding of new growth will kill pepperweed. Grazing is not
recommended because the plant may be toxic. Reestablishing the native or desired plants
can take years, so repeat plantings must be repeated, but it can aid in controlling
populations.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Biological control is not a viable option because 11 other species of native
Lepidium are on the Endangered species list, and the risk to these species as well as
agricultural species is too great.
d) Mechanical: Due to the deep, brittle root, most mechanical methods are not recommend,
and can actually propagate, spread and increase the density of pepperweed. Hand pulling
can also bring seeds to the soil surface, and spread pieces of root, which will sprout.
However, spring mowing combined with chemical treatments can be effective.
Comments: It is important to prevent establishment of large populations via early detection
and removal. Planting desirable and competing grasses and forbs is recommended
Herbicide treatments are a good option if used during the bud to flowering stage of the plant.
23. Russian -olive (Elaeagnus angusifolia) is a perennial tree or shrub that is native in Europe
and Asia. The plant has olive - shaped fruits, silver color at first then becoming yellow -red
when mature. Russian olive can reproduce by seed or root suckers. Seeds can remain viable
for up to 3 years. The plants extensive root system, sprouts root suckers frequently. The
lower surface is silvery white with dense scales, while the upper surface of the leaf is light
green in color. Previously thought to be a beneficial windbreak tree, it since has been
deemed detrimental to the environment because it competes native vegetation, interferes
with natural plant succession and nutrient cycling, and taxes water reserves. Russian olive
can grow in a variety of conditions. Although Russian -olive provides a plentiful source of
edible fruits for birds, ecologists have found that bird species richness is actually higher in
riparian areas dominated by native vegetation. The key to effective control of Russian olive
Town of Avon: Noxious Weed Management Plan
Page 12 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
is preventing establishment of the trees or shrubs. The state of Colorado mandates control
state -wide and requires eradication in most riparian areas. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
Biological: Tubercularia canker overwinters on infected stems and spreads via rain -
splash, animals, or pruning implements to open wounds in the bark. Infected tissue
becomes discolored or sunken. Entire stems may be girdled and killed, and the disease
can deform or kill stressed plants over time. For more information, contact the Colorado
Department of Agriculture's Insectary in Palisade, Colorado at 970 - 464 -7916.
d) Mechanical: Cut down the tree. Mowing with a brush type mower, followed by removal
of cut material, is another options for smaller shoot - hedges. Stump sprouting commonly
occurs after cutting down the tree, and excavation of the entire stump can trigger root
sprouting. Burning is practical when conditions support a long hot fire and most
effective in summer or early fall (burn permit required, call the Eagle River Fire
Protection District at 748 - 9665).
Comments: As a water conservation measure, Avon requires elimination of existing Russian
Olive trees from water courses but allows continued stand on higher ground where property
owners commit to control measures. Avon's weed management requirements on this
species are as follows:
• Removal is required if the tree is within 25 feet of the high water mark of a permanent
creek, stream, river; or within 25 feet of the top or rim of an irrigation canal, ditch or
ephemeral water course.
• Removal or control is allowed if tree is outside of water course boundaries.
A written commitment by the property owner or property manager for controlling the spread
of this species must be on -file to remain in compliance with Avon's Noxious Weed
Ordinance. Contact Avon Public Works, 500 Swift Gulch Rd, Avon 81620, call 970 -748-
4100 or by e -mail at weeds(a,avon.org.
Replacing with native trees is important once Russian olive has been removed, and is
required when the tree had previously been part of approved site landscaping. Contact Avon
Community Development at 970 - 748 -4030 for information about modifying your
landscaping plan.
24. Spurred anoda ( Anoda cristata) is a summer annual forb with a low growing, spreading
profile. The seedlings have one round and one heart- shaped cotyledon with hairs along the
margins of the leaves. The flowers appear August through November and are light blue to
lavender in color. Habitats include: ditches, within crops, along roadsides, gardens, waste
areas and disturbed sites. Spurred anoda is considered an agricultural weed and is found
mainly in agricultural crops (corn, cotton, beans, etc.). Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
Town of Avon: Noxious Weed Management Plan
Page 13 of 15
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
b) Chemical: N/A
c) Biological: N/A
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully as not to spread seeds.
Comments: Preventing seed production is key. Small patches can be controlled by hand
pulling or hoeing
25. Sulfur cinquefoil (Potentilla recta) is a perennial forb that is native to Eurasia. Leafstalks
have conspicuous perpendicular hairs and leaves appear green on the underside; plants can
grow 28 inches in height. The flowers are pale yellow. Sulfur cinquefoil grows on dry
sandy, gravelly, and rocky soils. Bareground is prime habitat for weed invasions. It is important
to properly identify sulfur cinquefoil, since it resembles the native cinquefoils. Management
Methods:
a) Cultural: Increasing the competitiveness of native species can assist in preventing
establishment of Sulfur cinquefoil. Contact your local Natural Resources Conservation
Service for seed mix recommendations.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Biocontrol species have been used in trials, since Sulfur cinquefoil is similar
to strawberries though, the insects used are considered pests. For more information,
contact the Colorado Department of Agriculture's Insectary in Palisade, Colorado at
970 - 464 -7916.
d) Mechanical: Mowing is not effective, as new shoots will replace the cut steams. Hand
dig or pull when soil is moist is effective on small infestations. Be sure to dig up as
much of the root system as possible, especially since root fragments can produce new
plants.
Comments: Hand pulling or digging when infestations are small and the soil is moist
combined with use of herbicides has proven to be effective.
26. Venice mallow (Hibiscus trionum) is a summer annual forb that has a spreading profile and
is native to Europe. The seeds are dark brown and can remain viable for 50 years. The
cotyledons are round with hairy petioles. The stems are erect and hairy, growing to about 18
inches tall. The first true leaves have toothed margins and are alternate. Flowers are a light
sulfur to yellow color with a red to purple center which only last a couple of hours. Venice
mallow is an agricultural weed. Management Methods:
a) Cultural: Outcompeting Venice mallow, is difficult with native grasses and forbs, since
Venice mallow likes agricultural crop areas. But, contact your local Natural Resources
Conservation Service for seed mix recommendations that may help in rangeland areas.
Bareground is prime habitat for weed invasions.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
Town of Avon: Noxious Weed Management Plan
Page 14 of 15
812712010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully so as not to spread seeds.
Comments: Best control is to prevent establishment of the plant and seed production with
early detection and physical removal. Herbicide treatments are another control option.
Multiple applications or a pre- emergence application will be most effective. When soils are
moist, hand pulling or digging is effective provided that you bag the removed plants.
V. Acknowledgements
The Town of Avon sincerely appreciates the great work done by botanists, scientists, and
others at the State of Colorado, Department of Agriculture and at the Colorado State
University Extension offices. These resources were the primary source of all of the
technical information contained in this plan. State and CSU staff reviewed this document
prior to the Town's 2010 adoption.
State of Colorado
Department of Agriculture
Noxious Weed Program
(303) 239 -4100
http://www.colorado.gov/cs/Satellite/Agriculture-Main/CDAG/I 174084048733
Colorado State University Extension
Eagle County Office
P.O. Box 239
441 Broadway
Eagle CO 81631
(970) 325 -8630
http: / /www.ea leg county.us /csu/
For more information, including color photos of all the species listed here, please
contact either of the above resources.
If you have general questions on noxious weeds or have received a noxious weed
violation notice, please call Avon Public Works at (970) 748 -4100.
Town of Avon: Noxious Weed Management Plan
Page 15 of 15
8/27/2010
TOWN OF AVUV
OFFTCAL ZONWG NAP
Adopped this am day of FeDnlsry, 2011. by Cf dio:nre I I -02
AQ.:
Maya' T— Cferk
i'
pC� (
ti3 (
1
x
PUD DISTRICTS
YUU NamMr
YUD Name
Date Approved
sa
I
N'Bdrtlge
1981 (Fuv l Plat. 2nd)
2
FaLwo Amrxation
1985 (O d. 8S-08)
3
Falcon Pomte
1985 (Ord. 65 -22)
%f1f/%L�a i/✓
Faglebend
1986 ((kd. 66 -12)
5
cry
1986 (lkd. 88 13)
6
%VIdMge Acres
1990 (Old. 90 -15)
7
Fou 4 PUD
1993 (OW. 93 -04)
8
Mounlan Srm
1994 ((kd. 92 -21)
9
Weagal'
1994 (Old. 94 -10)
10
NSmnghent Stalron (A.-nd rr'nt 4)
r�� JI�fr6lj
ft y
r
11
lakeside Terrace
1995 ((kd. 95-24)
r r
As (a.k.e. 'Gate: S 'Ch— St. Claire -)
1996 ((ml. 96 -16)
13
Ch p l Square
1996 (O d. 96 -25)
14
The Cwn m Storrebridge
1997 ((rd. 97 -05)
15
Brooksrd' Park
1997 ((kd. 97-13)
18
Village ., Axon
1998 ((kd. 98-17)
17
Avon CmW It Beaver Creek, La B
1998 (Ord. 98-23)
18
Gm w. (BMBC /690 Noamgham Rd)
1999 (Ord. 99-04)
19
Pomt Vi— (7plex > 5x.f.)
c
20
Grandview at Wildrrdge
' �.%J� �'� Ifs ✓ . �' -
21
i
2000 ((kd. 00 -02)
22
1 �✓ r I'`Ir'" G�,.;�'�N/rw�l�,<�!'f /��� '>� �1 � ..� " � „.�f,"'
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2000 ((kd. 00 -05)
23
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.ff/�J q� /„ /f% ors^! �„2nN� Y,„;`if '" tJ% ✓"1�.�'� � '/, -��� �/' �'�
2001 ((kd. 01 -12)
24
Las 42 & 43 AIM 4 Wildridge (2 4plx -a3 dup.)
2002 ((rd. 02-1 l)
25
Damns PUD (2 dup. >3 s.f).
2002 (Ord. 02-12)
w.
M.ucin PUD (2 dup. - 4 v.()
2002 ((),d. 02-13)
27
Lot 61
2004 (Ord. 04-01)
28
Wectem Sage
2004 (Ord. 04-15)
29
Dr) Creek
2005 ((hd. 05-09)
TOWN OF AVUV
OFFTCAL ZONWG NAP
Adopped this am day of FeDnlsry, 2011. by Cf dio:nre I I -02
AQ.:
Maya' T— Cferk
i'
pC� (
ti3 (
1
x
PUD DISTRICTS
YUU NamMr
YUD Name
Date Approved
1
N'Bdrtlge
1981 (Fuv l Plat. 2nd)
2
FaLwo Amrxation
1985 (O d. 8S-08)
3
Falcon Pomte
1985 (Ord. 65 -22)
4
Faglebend
1986 ((kd. 66 -12)
5
Ri—id,
1986 (lkd. 88 13)
6
%VIdMge Acres
1990 (Old. 90 -15)
7
Fou 4 PUD
1993 (OW. 93 -04)
8
Mounlan Srm
1994 ((kd. 92 -21)
9
Weagal'
1994 (Old. 94 -10)
10
NSmnghent Stalron (A.-nd rr'nt 4)
1995 (Ord. 95-07)
11
lakeside Terrace
1995 ((kd. 95-24)
12
As (a.k.e. 'Gate: S 'Ch— St. Claire -)
1996 ((ml. 96 -16)
13
Ch p l Square
1996 (O d. 96 -25)
14
The Cwn m Storrebridge
1997 ((rd. 97 -05)
15
Brooksrd' Park
1997 ((kd. 97-13)
18
Village ., Axon
1998 ((kd. 98-17)
17
Avon CmW It Beaver Creek, La B
1998 (Ord. 98-23)
18
Gm w. (BMBC /690 Noamgham Rd)
1999 (Ord. 99-04)
19
Pomt Vi— (7plex > 5x.f.)
1999 (Okd. 99 -08)
20
Grandview at Wildrrdge
2000 (Ord. 00 -01)
21
St— Mm. Viaa, La C. A,.. Center
2000 ((kd. 00 -02)
22
Borg
2000 ((kd. 00 -05)
23
aatmn<•m
2001 ((kd. 01 -12)
24
Las 42 & 43 AIM 4 Wildridge (2 4plx -a3 dup.)
2002 ((rd. 02-1 l)
25
Damns PUD (2 dup. >3 s.f).
2002 (Ord. 02-12)
20
M.ucin PUD (2 dup. - 4 v.()
2002 ((),d. 02-13)
27
Lot 61
2004 (Ord. 04-01)
28
Wectem Sage
2004 (Ord. 04-15)
29
Dr) Creek
2005 ((hd. 05-09)
30
R 'carom
2006 (( d 06 -03)
31
Red H—
2009 ((rd. 09-07)
32
Buck Creed.
2009 ((kd. 09 -08)
33
GmWaf (I Can F 4 ap-1 ->2 Dup.)
2009 (O d. 09-14)
TOWN OF AVON
OFFICIAL ZONING MAP
Zoning Districts
Residential Duplex
dr Town Center
Residential Low Density
Industrial and Commercial
Residential Medium Density
' `r'' Public Facility
Residential High Density
Park
Residential High Density Commercial (Retired)
Open Space, Landscaping and Drainage
Neighborhood Commercial
Planned Unit Development
Shopping Center (Retired)
dF Planned Unit Development, Open Space
Mixed Use Commercial
%� Short Term Overlay
Avon Town Boundary
PUD Boundary
Roads
10 PUD Numher
1 -70
Rivers and Lakes
N
r sea t,em z,eeo
r...rx.r e..�..srmrrrrar�
MA.. rr4raFYar
a....n_ zrr.r
•
Memo
To: Honorable Mayor and Town Council
Thru: Larry Brooks, Town Manager
Legal Review: Eric Heil, Town Attorney
From: Jennifer Strehler, Director of Public Works and Transpo atio�s-
Date: October 26, 2010
Re: Ordinance No. 10 -18 Adopting Local Designation of Noxious
Weeds and Approval of the Updated Avon Noxious Weed
Management Plan
Summary:
• This meeting is a continuation of the public hearing held on October 12, 2010 to
consider proposed Ordinance 10 -18 and the associated updated Avon Noxious Weed
Management Plan. The public hearing was continued to receive and review comments
submitted by representatives of Traer Creek -RP, LLC and its affiliates. Second reading
of this ordinance and adoption of the updated management plan is proposed for this
meeting.
Previous Council Actions:
October 12, 2010 - Meeting continued from September 24, 2010.
September 24, 2010 - 1st Reading of Ordinance 10 -18 "An Ordinance Adopting local
Designation of Noxious Weeds" and motion to adopt a revised "Avon Noxious Weed
Management Plan" (updated plan dated August 27, 2010).
August 27, 2010 - Public Notice posted for Ordinance 10 -18.
July 13, 2010- Informational presentation on the progress of implementing Ordinance
10 -06 and associated noxious weed identification, control and abatement methods.
April 27, 2010 - 2nd Reading of Ordinance 10 -06. This ordinance was approved and
the motion to adopt the "Avon Noxious Weed Management Plan" passed.
April 13, 2010 - 1st Reading of Ordinance 10 -06 "An Ordinance Enacting Noxious
Weed Control Regulations ".
Background:
• Please see the detailed memo published for the September 24, 2010 Avon Town
Council meeting and the slides of the presentation given on October 13, 2010.
Page 1 of 3
Discussion:
Please see attached comments from Mr. Bill Kyriagis from Otten Johnson, Robinson, •
Neff + Ragonetti. The cover letter of this is dated October 6, 2010. Mr. Kyriagis
states that he has submitted these comments "on behalf of Traer Creek -RP, LLC and
its affiliates ( "Traer ") ". A summary and analysis of Mr. Kyriagis's comments is offered
below. No other public comments have been received.
In several places, Mr. Kyriagis states his desire for the Town of Avon to have a
fair, effective, rational, and consistent enforcement method regarding noxious
weeds. Town Staff believe that the program and enforcement methods are fair,
effective, rational, and consistent. Technical review comments provided by the
State Department of Agriculture and the Colorado State Extension Office
support the Town's position.
Mr. Kyriagis alleges that the Town 'did little or nothing to address such
failures ". This is incorrect. Town staff contacted property owners in person, by
mail, and by telephone. A total of 79 certified letters were sent out plus many
other non - certified letters. Copies of the communication ledger and all letters
and notices were made available to Traer.
Mr. Kyriagis commented that "many Avon property owners made no serious
efforts, if any, to comply ". This is incorrect. Avon Public Works weed
notification ledger identifies that 76 properties took action to address noxious
weeds out of the 79 properties that were notified. This represents a 96.2% •
positive response rate.
Mr. Kyriagis states that the Avon Noxious Weed Management Plan lacks
qualitative and quantitative standards for measuring compliance. Compliance is
already defined by the State of Colorado. Eradication is measured by the
absence (success) or presence (failure) of noxious weeds. Control and
suppression is measured by the absence (success) or presence (failure) of
seeds or new shoots of noxious weeds on the property.
Mr. Kyriagis requests clarification as to what an acceptable schedule is for
compliance. He suggests that the Town was acting arbitrarily to give his client
e.g., 2.5 weeks while waiting over 4 weeks for CDOT to take proper action
along I -70. On this point, the Town of Avon certainly would have preferred a
faster response from CDOT. But because a local government cannot lien state -
owned land, political pressure is really all that can realistically be applied. Avon
Public Works notified CDOT via certified mail, consistent with the Town's
notification process to other property owners.
Mr. Kyriagis claims that the Union Pacific Railroad had standing noxious weeds
adjacent to Traer properties. No photos were provided by Mr. Kyriagis to
document this allegation. The Town's records show that UPRR property within
the Avon Town Limits was chemically sprayed on June 23, 2010 by the Town's
contractor. Within a few days, these noxious weeds were dead and were not •
producing or distributing viable seeds.
Page 2 of 3
The Town received an open records request from Mr. Bill Kyriagis on September 7,
•2010 for information regarding the Noxious Weed management program. Town Staff
prepared copies of the requested public records. The requested public records have
been available for pick -up since September 17, 2010; however, as of the date of this
memorandum, representatives of Traer Creek have not picked up this information. It
appears that Mr. Kyriagis prepared his comments on Ordinance 10 -18 without the
benefit of the requested public records.
•
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Financial Implications:
No change.
Recommendation:
Staff recommends passage of Ordinance 10 -18 and approval of the updated Noxious
Weed Management Plan.
Motion:
"I move to approve Ordinance 10 -18, Series 2010, Adopting Local Designation of
Noxious Weeds."
"I move to approve adoption of the 'Avon Noxious Weed Management Plan' dated
August 27, 2010.
Town Manager Comments:
Exhibits:
• Comments submitted by Mr. Bill Kyriagis from Otten Johnson, Robinson, Neff +
Ragonetti on behalf of Traer Creek -RP, LLC and its affiliates
• Copy of Packet item from September 28, 2010
Page 3 of 3
October 6.2010
Bi-, CERTIFIED MAIL
RETURN RECEIP "1' REQUESTED AND EMAIL
(JSTREHLER @AVON.ORG; WEEDS @AVON.ORG)
Jennifer Strehler
Town of Avon
Director of Public Works
PO Boa 975
Avon, Colorado 81620
Re: Noxious Weeds and Ordinance No. 10 -18
Dear Ms. Strehler:
BILL E KYRIAGIS
303 575 7506
BKYRIAGIS @OTTENJOHN SON COM
l ant writing on behalf ol'Traer Creck -RP, L.LC and its affiliates ("Traer ") to submit comments c0llcel'11I110 the.
'town of Avon's (the "Town") proposed Ordinance No. 10 -18 (the `Proposed Ordinance "), and the related issue
of the Town's enforcement of its existing noxious weeds ordinance (tile '`Weeds Ordinance ").
As you know, Traer and other affiliated entities have previously written letters to the Town concerning
entorcenlent of the I owns Weeds Ordinance as It relates to Traer and also other property owners. Specifically.
I refer you to a July 7, 2010 letter from Brad Schacht to you, and a September 71 2010 letter from 111c to 'town
Attorney, F ric Heil, both of which letters (the "Letters ") are attached hereto and incorporated herein by this
reference. I respectfully request that you include this letter and the Letters into the public record for the
Proposed Ordinance.
As enforced this year by the 'town, the Weeds Ordinance falls far short of ensuring fair and effective
enforcement of noxious weeds mitigation. Enforcement of the Weeds Ordinance has been uneven, thus severely
Undermining the goal of mitigating noxious weeds on affected properties.
With respect to the Proposed Ordinance, it seems to essentially do nothing other than formally designate local
noxious weeds. It does not address any of Traer's previously expressed concerns, as it does not set forth
meaningful standards and guidelines that would ensure fair and effective enforcement of'noxlous weed
mitigation.
Given what happened this year, this is a problem, as it appears that many Avon property owners made no
serious efforts, if any at all, to address noxious weeds on their properties. In most cases, the Town did little or
950 SEVEI;, EEtd'1H Si::EET SUITE 1600 DENVER COLORADO 80202 P 303 825 8400 F 303 825 6525 OTTENIGHNSOI\.COM
DENVER ASPEN VAIL VALLEY STEAMBOAT SPRINGS
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Jennifer Strehler
October 5, 2010
Page 2
nothing to address such failures. This is a very serious issue for all property owners in the Town, as weed
mitigation is a futile exercise if conducted on a particular property while weed issues on neighboring properties
go unaddressed.
']'his relates to another problem with the Town's Weeds Ordinance, both as it currently exists. and given the
noxious weed management plan to be adopted pursuant to the Proposed Ordinance. "there are simply no
meaningful standards for measuring compliance with whatever it is that the Town may require. The noxious
weed management plan lists various methods of management for the various scheduled noxious weeds, but
provides no qualitative or quantitative standards concerning mitigation.
The Weeds Ordinance is similarly vague. For example, as set forth in Avon Municipal Code § 8.36.100(c), in
response to a Notice of Eradication, "the property owner shall comply with the terms of the notification of
eradication or shall submit a plan and schedule which is acceptable to the Toinn for the completion of the
management objective." (Emphasis added.) What kind of schedule will qualify as "acceptable to the "Town "?
As written, property owners have no way to reasonably know what is expected of them, and the lack of
standards creates a significant risk that the Town will not enforce its Weeds Ordinance in a rational and
consistent manner.
• Traer', concerns are not unfounded. This year, Tracr experienced firsthand the unfettered discretion with which
the "town has approached this issue. In one instance, without any basis, you personally set a wholly arbitrary
deadline of two- and -a -half weeks after the date of an initial Notice of Eradication for'Traer to remove every
single wecd from an enormous piece of property. This date was set notwithstanding the fact that, at the time you
set the deadline, Traer had a very large crew that was actively cutting, spraying and mowing on the property. At
the saute time that you conveyed your conclusion that Traer's significant efforts were simply not good enough,
the 'Town was content to allow CDOT's properties to go at least one month without a»v attention to noxious
weed issues whatsoever. Similarly, no action was ever taken against Traer Creek Metropolitan District, despite
the T'own's having identified a number of noxious weeds issues on its properties during this same general
tintefrante. With regards to Union Pacific, in vour.luly 13, 2010 presentation to the Avon'I'mN.11 Council, you
stated that Union Pacific's property had been mitigated and would require one more go al'OUnd later in the
sunu»er. Contrary to your comments. Union Pacific's property had not been full\. mitigated and. in fact. had
areas infested with Canada Thistles and other noxious weeds that were within tell feet ofthe lot line of Traer
Property.
The referenced entities' properties border on Traer's property, so their behavior is of particular concern to Traer.
However, all property owners in the Town should have similar concerns. Observation of conditions this year
revealed that there was little, if any; noxious weed mitigation efforts made on significant portions of the
property within the "Town.
If this pattern continues, it will likely severely undercut the willingness of property owners to engage in noxious
weed mitigation efforts on their own properties, and will render the entire process ineffective. Noxious weed
management efforts can be quite expensive. In order to be fair and effective, the Town must have a system that
ensures equal treatment. The case of CDOT provides an example, since it appears that the Town considered it
sufficient for CDOT to mow its lands once or twice during the entire summer. If the Town considers this to he a
sufficient level of mitigation efforts for some property owners, that level of mitigation efforts should be
•
Jennifer Strehler
October 5, 2010
Page 3
considered sufficient for all property owners. Without adequate standards to measure progress and against
which to test compliance, there is a significant risk that the Town's future enforcement efforts will unfairly
burden particular property owners. This is both unjust, and undercuts the purported ultimate objective of
implementing an effective noxious weed mitigation program throughout the Town.
Accordingly, Traer urges the ']'own to consider and enact further changes to its Weeds Ordinance that will
ensure that its weed management program is effective, fair and enforced in an evenhanded and
nondiscriminatory manner.
Sincerely,
Bill E. Kyriagis
for the Firm
BEK
750 "451 J
cc: Eric Heil, Esq. (by Email)
Thomas J. Ragonetti, Esq. (by Email)
Munsey L. Ayers, Esq. (by Email)
Brad W. Schacht, Esq. (by Finail)
Frances A. Koncilja, Esq. (by Email)
Marcus Lindholm (by Email)
Michael Lindholm (by Email)
Dan Leary (by Email)
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f2UlIS)JN NC(=F 1?AGON rTi.
July 7, 2010
BY CERTIFIED MAIL
IZETURN RF.Ct?INT REQUESTED AND EMAIL
(Js'1'RENLIiItCa,)AVON.ORC; WEEDS@?,AVON.OR(;)
Jennifer Strehler
Director of' Public Works
500 Swift Gulch Road
Avon, CO 81620
BRAD W SCHACHI
303 575 7527
BRAD(POTTENJOHNSON COM
Re: Notice of Noxious Weed Violation Dated July 1, 2010
• Dcar Ms. Surchler:
am writing in response to the Notice ol'Noxious Weed Violation dated JUIv 1, 2010, and scat to Traer (:reek -
RP, LI,C ("Traer -RP ") (the "Notice "). The Notice alleoes "noxious weed" violations lur certain identified
properties (the "Properly ").
I would first like to note that the Notice was, at least partially, addressed incorrectly pursuant to the Town of
Avon's ( "Town ") ordinance. ,See Avon Municipal Code ("AMC ") § 8.36.100(a) (requiring that notices of
eradication be sent by certified mail to the: property owner at the address of record according to the Eaglc
County Assessor's Office). Traer -RP is not the owner of record of all of the Property. For example, Traer
Creek Plaza, LL.0 ("Traer Plaza ") is the owner of the property described as Lot 2, Filing I, Village at Avon (the
"Plaza Property "). The Notice was not sent to Traer Plaza's attention, though Traer Plaza has already removed
any "noxious weeds" from the Plaza Property. These issues have been brought to the Town's attention in the
past. For clarity, the various owners of the Property are referred to herein as the `'Owners."
Regardless of the validity of the mailing of the Notice, as VOL] are aware, the principals of the Owners of the
Property, Magnus, Marcus and Michael Lindholm, are currently in Sweden attending the funeral of Magnus
L.indholm's mother. In their absence. it is difficult for the Owners to address this issue. We expect the
Lindholms to return some time during the week of July 11. In these circumstances, we would ask that the
Owners be afforded additional time to evaluate the issue, and formulate a more complete response.
That said, my initial evaluation ofthe situation reveals a number of'relevant issues. Some of the Property
identified in the Notice is located south of 1 -70 (the "Southern Property ") and some of the Property is located
north of 1 -70 (the "Northern Property "). Generally speaking, significant questions remain concerning the
"T'own's authority to impose "noxious weed" management requirements on the Owners, whether under the State
• 7;., Sc, ..��_n:TH "F. E' Sly' I C0 - ENVE .;0! .I;A,O &C:',2 P .,.,� �tif:, �,... ^3 ._ �'..- .'CN C01.
DEA "!Ea k J::II. `J::LL'eY >TFptluOAI SDR';tfS
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Jennifer Buehler
July 7, 2010
Page 2
statute or the Town's ordinance. Aside from anv regtllatoty requirements, in the context of the Southern
Property, the Owners view wood management as but one component ()fall overall program of sound land
management and ownership practices. 'This, and not Town compulsion or authority, is the reason that the
Owners have been actively addressing weeds on the Southern Property. Indeed, before the Notice was even sent
out, the Owners were already actively engaged in "noxious weed" mitigation efforts on u// 01'1111C Southern
Property. Tracr -RI' previously submitted a Noxious Weed Management Plan for Lot I, Filing, 1 village at
Avon, which the Owners continue to apply to the rest of the Southern Property. Accordingly, with respect to the
Southern Property, it does not appear that the Notice was even necessary here. I have confirmed with the
(},vners' on -site agents that their of sorts are nearly complete, but as of yesterday, they wore still actively
engaged in continued "noxious weed" mitigation activities on the Southern Property. You nlav have seen them;
they had a very large crew of workers engaged in these efforts.
Unlike the Southern Property, which is essentially surrounded by development, the Northern Property presents a
vastly different set of circumstances. Indeed, the situation with respect to the property neighboring the Northern
Propertv may make weed mitigation or management on the Northern Property a completely futile exercise. The
Northern Property borders on Town rights -of -way, e.g., Swift Gulch Road, and /or the CDOT right -of -way liar I-
70. As you know, motor vehicles and rights -of -way are likely the primary vector by which weeds are spread,
and it does not appear that "noxious weeds" have been fully eliminated from these rights -ol -way. In recognition
of'this issue, the State prohibits the Town from taking "Illy action a-gainst private property until it first applies the
same or greater management nlcasures to any land or rights -ol'-wav owned or administered by the hown that arc •
adjacent to the private property at issue..Sec C.R.S. § 35- 5.5- 108.5(9)(b); C.R.S. § 35- 5.5- 109(5)(6). Making
matters worse, the North Property is essentially surrounded by U.S. Forest Service farad. Obviously• the fawn
and the State 118ye no authority to compel the Federal Government to address "noxious weeds' rnt its property,
and it is my understanding front local contacts and contacts in the industry that the Forest Service essentially
does nothing to manage -- noxious weeds" on its lands. The Town cannot reasonably expect the Owners to
maintain a weed -free island surrounded by a sea of neglected and unmitigated weed - filled lands.
Furthermore, in the context ofthe State's overall "noxious weed" management program, the `noxious weeds"
allegedly identified on the Northern Property are not particularly "noxious." With respect to the Northern
Property, the Notice identified only four "noxious weeds ": Canada Thistle, Musk Thistle, 1-loundstongue, and
Yellow Sweet Clover. None of'these "noxious weeds" is included among the State ol'Colorado's List A
species, all of'which are designated for eradication, nor are they included among those List (3 species designated
for eradication in Eagle County. Sect 8 C.C.R. 1206 -2, Part 4.10.7 (houndstonoue not designated for eradication
in Tingle COMM ). Indeed, the State of�Colorado has not even developed "noxious weed" management plans Ior
Canada Thistle Or Musk Thistle, and Yellow Sweet Clover is not even on the State's list of'desionated "noxious
weeds.'.
As you know, the Northern Property is undeveloped land, essentially surrounded by wilderness and rights -of-
way. The Owners actively use the Northern Property to graze sheep, and these sheep are sold for human
consumption. The Owners are thus very concerned about the use of any chemical agents on their Property. The
Owners also have practical concerns about the effectiveness, safety and economic feasibility of '`noxious weed"
manai7ement activities on the rough, steep terrain that makes up the Northern Property. W1111c they have not vet
had a full opportunity to evaluate all of the circumstances, the Owners are not inclined to endanger the health
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Jennifer Strehler
July 7, 2010
Page 3
and safety of their employees and a"cnts, or that ui-thcir livestock in ;rn effort to miti,,;uc . lloxioll; weeds" oil
the Northern Property. They arc especially reluctant to do so considering that the Northern Property is
surrounded by other lands infested with the same '`noxious weeds," since the circumstances with respect to those
lands is not likely to change. In this context, what the 'town is appearing ro require is simple not a component
of-'sound land nrtnagentent and ownership practices.
In light ol' the overall circumstances, illy initial conclusion is that eradication of the '•noxious weeds" identified
III the Notice on the Norlhern Property is not economically feasible, safe, or- prudent, let alone required.
I lowever, in light of'the absence of the O\vncrs' principals, we request that you allow the Owners additional
time to respond to the Notice. With respect to the Southern Property, the Owners were proactively addressing
"noxious weeds" and were thus already in compliance with the Notice before it was sent. If the Town simply
needed to have a Noxious Weed Management Plan on file for the Southern Property, the Plan previously
provided for Lot 1, Filing 1, Village at Avon is sufficient.
The identified "noxious weeds" have been present throughout Eagle County for decades ---- -lone before illy
clients' representatives left for Sweden to attend the funeral of their mother /grandmother. 'I'hcse `'noxious
weeds" Will SnrCIV remain on the Forrest Service land for decades to come. Accordingly, I rcqucst that y(xr
allow additional time for the I.indholnts to return so that the 01,vners can have an adequate opportunity to
address this issue directly. Additionally, considering my clients' cm-rent unavailability, please advise ntc prior
• to taking any enforcement action against the Property or the Owners. Thank vou.
Sincerely,
Brad W. Schacht
for the Firm
BWS
VS iili I
cc: Eric Heil, Esq. (by Email)
,Fhontas J. Ragonetti, I sq. (by Email)
Munsey L- Ayers, Esq. (byF,mail)
Bill E. Kyriagis, f sq. (by Entail)
Magnus Lindholm (by Email)
Marcus L.indholrn (by Entail)
Michael Lindholm (by Entail)
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ROBINSON t,4EFF +RAG0NETTI,,
September 7, 2010
BY CERTIFIED MAIL
RETURN Rec►:mr R►•QUFSTeo AND FIMAll.
(ERICHElLLAw(«Gl�ukI1 -com)
Eric Hcil
`Down Attorney - Town of Avon
Heil Law & Planning, L LC
1499 Blake Street, Unit I -G
Denver, CO 80202
Re: Notices of T:nty and Inspection Dated August 20. 2010
Dear Eric:
DILL L KYRIAGIS
305 575 7506
BKYRIAGISgO I'1 ENJOHNSON COM
I am Writing to 1`0110W up on our conversation from Thursday, and regarding the Town of' Avon's ( "'town ")
Notices of' Entry and Inspection dated August 20, 2010 (the "Notices "), and sent to this firm's clients, Traer
Creek -RP LLC, Traer Creek -1-2 LLC, Traer Creek -WMT LLC, Traer Creek -FID LLC, and Alkali Company
(collectively, "Traer'). The Notices were sent pursuant to Avon Municipal Code ("AMC ") § 8.36.100(a) and
they sough( permission to enter and inspect certain property that Traer owns, as more particularly described in
the Notices (the "Property ").
As you know, my clients have been actively engaged in significant weed management el'lorts for the past 1Cw
months. This includes weed management efforts undertaken on the Property. These efforts have been ongoing.
and in the coining days, sheep Will begin Crazing on the Property, as they have in the past. The sheep will have
a significant impact on any remaining weeds on the Property, as the Sheep cat weeds. It should also be noted
that the presence of grazing sheep influences and constrains the scope of other weed management el'forts that
can be applied on the Property. Given that the sheep eat weeds, chemical spraying is simply not a reasonable
weed management technique, and overly aggressive cutting may deprive the sheep of adequate feed. In fact,
there isn't enough feed for the sheep this year, due to this kind ol' overly aggressive cutting. "1`ITese issues will
remain relevant in coming years.
In our conversation, you and I discussed the possibility of arranging consensual inspections of the Property.
However, 'Thursday, you also sent me a Notice 0f Public Hearing Regarding Declaration of Additional Noxious
Weeds (the "Hearing Notice "), which states that the '['own intends to declare the weeds listed therein as noxious
Weeds. Given the timing, and based on 01.11• Conversation, it seems that the Town will not be requiring further
weed mitigation ellorts Irom property owners this year.
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950 CLVEN", cNTiI STREET SUITE 16OC DENVER COI 0RADc E02C2 P 303 S 25 P. oo F 3r,'3 25 652E 0 TTE1;J011N807J.00A9 •
DENVER ASPEN VSIL VALLEY STEAMBC,1T SPeINGS
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Eric Heil
September 3, 2010
Page 2
After our conversation, I had an opportunity to confer with my clients. In the circumstances, we feel that the
requested inspections arc without basis, and without purpose' Notices do not specify the basis for the
requested inspections, and there is no apparent basis for the inspections. Given that the Town will not be
requiring further Weed mitigation efforts this year, the requested Inspections also seers to have no purpose.
Further, the Notices quote AMC § 8.36.100(a), which allows the Town to seek an inspection warrant "ill
accordance with C.R.S. § 35- 5.5- 108.5(4)(b)" if a property owner does not respond to i notice u1- inspection or
denies access. However, by its terms. C.R.S. j 35 -5.5 -108.5 only applies "to noxious weeds that have been
classified as list A species and to populations of list 13 species designated f'or eradication pursuant to section
35/5- 108(2)(a)." As we discussed Thursday, the Town has never identified any list A species on Traer's
Properly, nor any list 13 species designated for eradication in Eagle County pursuant to C.R.S. S 35 -5.5-
108(2)(x). (`Moreover, C.R.S. § 35- 5.5- 108.5(4)(b) is not even a provision that addresses issuance of inspection
warrants.
In the absence of further information suggesting that an inspection 01' the Property is, in fact, authorized
pursuant to law, we are not inclined to consent to the requested inspections. phis decision is also informed by
the history here. In June and July of this year, the Town began cl7orls to impose weed nutnagcmcnt
requirements on Trier. When I told VOL] on July 22, 2010, that 111\1 client's representatives would be in Avon
and prepared to meet and discuss the weeds issues in early ALli;tlsl, you responded that yuu suspected "that a
• time frame of 'early August` for the property owner(s) to determine to evaluate the existing conditions internally
will not be satisfactory for the 'Town.'' You also said you would get back to me early the week ol'July 26, ?010
+ith any response by the 'Down. Despite the expressed urgency, you never contacted me. Indeed, the next I
heard front you on the weeds issue was your email oil August 23, 2010 transmitting the Notices. Those Notices
represented the beginning of an entirely new process, completely unrelated to the process from .June and .July.
In the Hearing Notice and during our conversation `fhursday, you essentially acknowledged that the Town is
starting over on the process. Accordingly, it appears that Tracr has been subjected to unnecessary and
unjustified pressure from the Town to address noxious weeds on their properties. Even minimal observation of
the conditions throughout the Town indicates that there are unabated noxious weeds on a significant number of
properties in Town. Along with the Notices. you also sent nne seventeen other notices that were addressed to
entities that this firm does not represent. relating to properties not owned by my clients. In .June, Jennilcr
Strehler also told Michael Lindholm that the Town had sent noxious weeds notices to six other property owners
in "Down. Accordingly, 1 know that the Town has sent notices, but I question whether the Town has vigorously
followed up on such notices.
All the evidence available at this time indicates that the Town has been singling Traer out for aggressive weed
enforcement, while doing relatively little to address other properties in 'row•n. One instance of the Town's
aggressiveness toward my clients is illustrative. On June 11, 2010, the Town sent a notice of noxious weed
eradication to Traer Creek -RP LLC concerning Lot I of the Village (at Avon) Filing 1. Traer informed the
'Down on June 18, 2010 that a significant anwunt of work had already been perforated on I,ot I, and invited
Jennifer St•ehler or other 1 -own representatives to visit the property with a 'Traer representative to see the
progress that had been made to that point. On June 23. 2010, Ms. Strehler wrote 111 email to Michael Lindholm
stating that she had observed Lot I the previous day and `lots of noxious weeds" were still on it.
•
Eric Heil
September 3, 2010
Page 3
Acknowledging that Traer had submitted a noxious weed management plan and had been actively engaged in
weed management efforts, Ms. Strehler stated that all the weeds should have been removed by that time. She
also set an arbitrary deadline of June 30, 2010 for all of-the weeds on Lot I to be removed. There is simply no
authority in the state statute or Town ordinance for setting a deadline to have every single weed removed from a
property two - and -a -half weeks after a notice to eradicate is first issued, especially for a property as large as
Lot 1. Regardless, Ms. Strehler stated that, if' her deadline were not met, the 'Town Would enter Lot I and use
chemical sprays, mowing and trimming to remove the weeds itself.
I -las the Town conducted any formal inspections of properties for noxious weeds'? Has the Town pursued and
obtained inspection warrants for other properties in "town'? Has tile Town set deadlines oftwo-and-a-half weeks
For the absolute eradication of every single weed on any other property in town? Has the Town entered anv
Private property to abate weeds where the property owner Was unresponsive or unwilling to abate weeds on his
or her property? I las the "Town even threatened to do so'? Particularly, in the case of Traer's neighbors, has the
Town taken any significant action with respect to noxious weeds management for property owned by the
Colorado Department of' Transportation. Union Pacific Railroad or the Traer Creek Metropolitan District?
Significant portions of my clients' property border on lands owned by these entities, and if' these property
owners are not controlling the weeds on their lands, it will be absolutely Iluile for my clients to attempt to do so
on their properties.
Gcncrally, the Town needs to coordinate the effort to miti`,ate noxious Weeds, and this effort needs to be Tntirrr
;V&e .
In addition to this letter; 'Ilaer intends to submit an open records request to the Town, seeking further
information on the "town's efforts to enforce noxious weed management requirements on property owners in the
Town. Information produced in response to that request should shed additional light on wllethcr the Town has
been pursuing the weeds issue in an evenhanded fashion.
Sincerely,
Bill E. Kyriagis
for the Firm
131: K
cc:
Thomas J. Raoonetti, Esq. (by Firnail)
Munsey L. Ayers; Esq. (by Email)
Brad W. Schacht , Esq. (by Email)
Frances A Koncilja. Esq. (by Entail)
Magnus Lindholm (bv Email)
Marcus Lindholm (by Email)
Michael Lindholm (by Email)
Dan Leary (by Entail)
•
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Memo
To: Honorable Mayor and Town Council
Thru: Larry Brooks, Town Manager
Legal Review: Eric Heil, Town Attorney
From: Jennifer Strehler, Director of Public Works and Transportation
Date: -Septo 3� ) O 1 U
Re: Ordinance No. 10 -18 Adopting Local Designation of Noxious
Weeds
Summary:
Town Council originally passed an ordinance in April 2010 amending the town code
•regarding noxious and nuisance weeds. Approval of the ordinance is now needed to
fulfill a state requirement regarding a 30 -day public notice period. Public notice for
this September 28th hearing was posted on August 27, 2010 at the Town's customary
public notice locations. Also the associated noxious weed management plan has been
amended to add several weeds designated by the state for control or eradication in
Eagle County which were previously not included. A motion approving of the updated
management plan ;is also needed.
Previous Council Actions:
On April 13, 2010, Town Council discussed proposed Ordinance 10 -06, "An Ordinance
Enacting Noxious Weed Control Regulations" which revised § §8.24.046 of the Avon
Municipal Code entitled "Undesirable Plants" (1992) and also § §8.24.045 entitled
"Weeds" (1983). It was approved upon first reading but with the request that the
originally proposed language regarding non - noxious but nuisance weeds and grass
mow heights be removed. Staff made these changes and submitted a revised
ordinance for consideration on April 27, 2010.
On April 27, 2010, a public hearing was held regarding Ordinance 10 -06. The Town
Council approved Ordinance 10 -06 upon second reading. The new ordinance language
can be found in §8.36 of the Avon Municipal Code.
Town received communications disputing the Town's legal authority to enforce locally
designated noxious weeds. Although the Town did post notice of Ordinance No. 10 -06
• Adopting Noxious Weed Regulations 30 days prior to the first reading of Ordinance No.
10 -06; the Town Attorney has recommended that the Town re- notice the local
designation of noxious weeds.
Page 1 of 4 Council Memo
Memo
To: Honorable Mayor and Town Council
Thru: Larry Brooks, Town Manager
Legal Review: Eric Heil, Town Attorney
From: Jennifer Strehler, Director of Public Works and Transportatioroq_/�
Date: September 24, 2010
Re: Ordinance No. 10 -18 Adopting Local Designation of Noxious
Weeds
Summary:
Town Council originally passed an ordinance in April 2010 amending the town code
regarding noxious and nuisance weeds. Approval of the ordinance is now needed to
fulfill a state requirement regarding a 30 -day public notice period. Public notice for
this September 28" hearing was posted on August 27, 2010 at the Town's customary
public notice locations. Also the associated noxious weed management plan has been
amended to add several weeds designated by the state for control or eradication in
Eagle County which were previously not included. A motion approving of the updated
management plan is also needed.
Previous Council Actions:
On April 13, 2010, Town Council discussed proposed Ordinance 10 -06, "An Ordinance
Enacting Noxious Weed Control Regulations" which revised § §8.24.046 of the Avon
Municipal Code entitled "Undesirable Plants" (1992) and also § §8.24.045 entitled
"Weeds" (1983). It was approved upon first reading but with the request that the
originally proposed language regarding non - noxious but nuisance weeds and grass
mow heights be removed. Staff made these changes and submitted a revised
ordinance for consideration on April 27, 2010.
On April 27, 2010, a public hearing was held regarding Ordinance 10 -06. The Town
Council approved Ordinance 10 -06 upon second reading. The new ordinance language
can be found in § §8.36 of the Avon Municipal Code.
•
•
Town received communications disputing the Town's legal authority to enforce locally
designated noxious weeds. Although the Town did post notice of Ordinance No. 10 -06
Adopting Noxious Weed Regulations 30 days prior to the first reading of Ordinance No. •
10 -06; the Town Attorney has recommended that the Town re- notice the local
designation of noxious weeds.
Page 1 of 4 Council Memo
Background:
• The Colorado Noxious Weed Act §§ 35- 5.5.101 through 119 (CRS 2003) requires local
governments to rules set forth in 8 CCR 1206 -2 and in the Act to control the spread of
noxious weeds. The state requires counties, cities, and towns to adopt a specific
noxious weed management plan. Avon is compliant this regard, with the Town
Council acting as the local Weed Management Advisory Commission.
A copy of the public notice posted for this hearing is attached. This notice was posted
on August 27, 2010 at the Town's customary public notice locations.
Discussion:
Avon's Noxious Weed Management Plan includes all of the state's List A species plus
the species listed below. Species ID # 18 -26 have been added to Avon's plan since
the previously approved April version. These were added because they are identified
for control or eradication in Eagle County in 8 CCR 1206 -2. In the event the state
adds another species to List A or to List B with an explicit requirement for eradication
in Eagle County, Avon's management plan "automatically updates" to include such
added species.
Management Method #
Common Name:
Scientific Name:
1
Leafy Spurge
Euphorbia esula
2
Russian Knapweed
Acroptilon repens
3
Diffuse Knapweed
Centaurea diffusa
4
Spotted Knapweed
Centaurea maculosa
• 5
Canada Thistle
Cirsium arvense
6
Musk Thistle
Carduus nutans
7
Plumeless Thistle
Carduus acanthoides
8
Scotch Thistle
Onopordum acanthium
9
Houndstongue
Cynoglossum officinale
10
Whitetop /Hoary Cress
Cardaria draba
11
Yellow Toadflax
Linaria vulgaris
12
Oxeye Daisy
Chrysanthemum leucanthemum
13
Dalmatian Toadflax
Linaria dalmatiaa
14
Common Tansy
Tanacetum vulgare
15
Scentless Chamomile
Matricaria perforate
16
Salt Cedar
Tamarix chinensis
17
Yellow Sweet Clover
Melilotus officinalis
18
Black henbane
Hyoscyamus niger
19
Bull Thistle
Cirsium vulgare
20
Chinese clematis
Clematis orientalis
21
Eurasian watermilfoil
Myriophyllum spicatum
22
Perennial pepperweed
Lepidium latifolium
23
Russian -olive
Elaeagnus angusifolia
24
Spurred anoda
Anoda cristata
25
Sulfur cinquefoil
Potentilla recta
• 26
Venice mallow
Hibiscus trionum
At a minimum, the state
requires the local authority to eradicate all of the List A
Page 2 of 4 Council Memo
species and either eradicate or control all List B species. Some List B species are
more or less of a threat in a particular geographic area, as described in 8 CCR 1206 -2. •
It is important to understand that the state's rules and regulations regarding noxious
weeds and best management practices are still evolving. For example, at the time of
adoption of 8 CCR 1206 -2, the state did not have a formal management approach to
all List B species (e.g., Canada thistle, Russian Olive). Since that time, federal, state,
and county best management practices have been developed. In using the term
"control," the state rules may mean either "elimination of all populations" or
"suppression ", with the distinction depending on the specific plant and a specific
geographic area.
Local home rule authorities are legally empowered to include additional species in the
locally managed noxious weed list. Local governments are not limited by state law to
regulate only those plants on the state's List A, B or C. Also, Local governments do
not need to wait for the state to publish their plan for management of a particular
species in order to take local action.
Yellow Sweet Clover ( #17 in list above) is the only species on Avon's designated
noxious weed list that is not currently included on any of the states A, B or C list. This
plant is highly prevalent on many disturbed or poorly re- vegetated sites in Avon.
Town staff originally included this plant in the April list because technical sources
report it to be invasive, produce over 100,0000 seeds per plant, outcompete native
vegetation, cause anti - coagulation properties in the blood of grazing animals, and be
very high in pollen.' Eagle County's Weed Coordinator, Tim Girard, commented that •
this plant has been used in re- vegetation mixes and can be beneficial for bee keepers.
Weed While Avon staff recognize this, they recommend continued inclusion of this
species in Avon's noxious weed list due to all of its other negative attributes.
Financial Implications:
No change.
Recommendation:
Staff recommends passage of Ordinance 10 -06 and approval of the updated Noxious
Weed Management Plan.
Motion:
"I move to approve Ordinance 10 -18, Series 2010, Adopting Local Designation of
Noxious Weeds."
Town Manager Comments:
This species is listed as invasive in 26 states including Colorado, Arizona, Texas, Wyoming, and Utah. See:
U.S. Forest Service. Weed of the Week: Yellow Sweetclover. Accessed February 2009:
http: / /www.na.fs.fed.us /fhp /invasive plants /weeds /vellow sweetclover.pdf •
Whitson, T.D. (ed.) et al. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative
Extension Services, University of Wyoming. Laramie, Wyoming.
United States Department of Agriculture, Accessed online on April 8, 2010 at
http: // Plants. usda ..qov /iava/profile ?sym bol =MEOF.
Page 3 of 4 Council Memo
U
U
•
Exhibits:
• Copy of Notice
• Ordinance No.
• Exhibit A: Nox
10 -18 Adopting Local Designation of Noxious Weeds
pus Weed Management Plan to Ordinance No. 10 -18
Page 4 of 4 Council Memo
NOTICE OF PUBLIC HEARING REGARDING DECLARATION OF ADDITIONAL
NOXIOUS WEEDS •
Notice is hereby given, that the Town Council of the Town of Avon, shall conduct a public hearing
at the Avon Town Hall, located at One Lake Street, Avon, Colorado, on September 28h, 2010, at
5:30 p.m. or as soon thereafter as possible, regarding the designation of additional noxious weeds.
Written comments may be e- mailed to Avon Public Works weeds(2(avon.org or may be mailed to
Town of Avon, P.O. Box 975, Avon, CO 81620. Written comments received by September 22,
2010 shall be included in the Town Council materials for their review and consideration. Copies of
the Town of Avon Noxious Weed Management Plan may be obtained from the Town Hall during
normal business hours or by Gary Padilla, Avon Road and Bridge Superintendent, Avon Public
Works (970) 748 -4100 or via e -mail at weeds@avon.org.
The Town of Avon has adopted by reference the List A species as designated by the State of
Colorado, Department of Agriculture, in 8 CCR 1206 -2. The authority for local declaration of
noxious weeds is pursuant to the Colorado Noxious Weed Act, Article 5.5, Title 35, Colorado
Revised Statute, Ordinance No. 10 -06 AN ORDINANCE ENACTING NOXIOUS WEED
CONTROL REGULATIONS, and by the Town of Avon's home rule authority.
The declaration of additional noxious weeds includes:
Black henbane (Hyoscyamus niger)
Bull Thistle (Cirsium vulgare) •
Canada thistle (Cirsium arvense)
Chinese clematis (Clematis orientalis)
Common tansy (Tanacetum vulgare)
Dalmatian toadflax, broad - leaved (Linaria dalmatica)
Diffuse knapweed (Centaurea diffusa)
Eurasian watermilfoil (Myriophyllum spicatum)
Hoary cress (Cardaria draba)
Houndstongue (Cynoglossum officinale)
Leafy spurge (Euphorbia esula)
Musk thistle (Carduus nutans)
Oxeye daisy (Chrysanthemum leucanthemum)
Perennial pepperweed (Lepidium latifolium)
Plumeless thistle (Carduus acanthoides)
Russian knapweed (Centaurea repens)
Russian -olive (Elaeagnus angusifolia)
Salt cedar (Tamarix chinensis, T.parviflora, and T. ramosissima)
Scentless chamomile (Matricaria perforata)
Scotch thistle (Onopordum acanthium)
Spotted knapweed (Centaurea maculosa)
Spurred anoda ( Anoda cristata)
Sulfur cinquefoil (Potentilla recta)
Venice mallow (Hibiscus trionum) •
Yellow sweet clover (Melilotus officinalis)
Yellow toadflax (Linaria vulgaris)
Copy of Notice
• TOWN OF AVON, COLORADO
ORDINANCE 10 -18
SERIES OF 2010
AN ORDINANCE ADOPTING LOCAL DESIGNATION OF NOXIOUS WEEDS
WHEREAS, the Town of Avon ( "Town ") is a home rule authority municipal corporation and
body politic organized under the laws of the State of Colorado and possessing the maximum
powers, authority and privileges to which it is entitled under Colorado law; and
WHEREAS, the Town Council is authorized to declare nuisances, establish fines and
penalties, and require abatement of public nuisances pursuant to its home rule authority and
pursuant to Colorado Revised Statute §31- 15- 401(1)(c); and
WHEREAS, the Town Council is authorized to provide for the removal of weeds pursuant to
Colorado Revised Statutes §31- 15- 401(1)(d); and
WHEREAS, the Town Council is authorized to implement and enforce the Colorado
Noxious Weed Act, C.R.S. §35 -5.5 -101 et. seq.; and
WHEREAS, C.R.S. §35 -5.5- 108(3) provides that the governing body of a municipality may
declare additional noxious weeds after a public hearing with thirty days notice to the public; and
WHEREAS, notice of the local designation of noxious weeds was posted on August 27,
• 2010 in accordance with requirements in Home Rule Charter of the Town of Avon; and
WHEREAS, it is the Town Council's opinion that the health, safety and welfare of the
citizens of the Town of Avon would be enhanced and promoted by the adoption of this
ordinance; and
WHEREAS, approval of this Ordinance on first reading is intended only to confirm that the
Town Council desires to comply the requirements of the Avon Home Rule Charter by setting a
public hearing in order to provide the public an opportunity to present testimony and evidence
regarding the application and that approval of this Ordinance on first reading does not constitute
a representation that the Town Council, or any member of the Town Council, supports, approves,
rejects, or denies this ordinance;
NOW THEREFORE, BE IT ORDAINED BY THE TOWN COUNCIL OF THE TOWN
OF AVON, COLORADO, the following:
Section 1. Recitals Incorporated. The above and foregoing recitals are incorporated herein by
reference and adopted as findings and determinations of the Town Council.
Section 2. Adoption of Local Designation of Noxious Weeds. The Town Council, as the
governing body of the Town of Avon, hereby adopts the local designation of noxious weeds as
such weeds are set forth in the Town of Avon Noxious Weed Management Plan, dated August
27, 2010, attached hereto as Exhibit A.
Section 3. Noxious Weed Management Plan Adopted. The Town of Avon Noxious Weed
• Management Plan, dated August 27, 2010, attached hereto as Exhibit A is hereby adopted in its
entirety.
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 1 of 3
V1 9.22.10
Section 4. Codification Amendments. The codifier of the Town's Municipal Code, Colorado •
Code Publishing, is hereby authorized to make such numerical and formatting changes as may be
necessary to incorporate the provisions of this Ordinance within the Avon Municipal Code. The
Town Clerk is authorized to correct, or approve the correction by the codifier, of any
typographical error in the enacted regulations, provided that such correction shall not
substantively change any provision of the regulations adopted in this Ordinance. Such corrections
may include spelling, reference, citation, enumeration, and grammatical errors.
Section 5. Severabilit_y. If any provision of this Ordinance, or the application of such provision
to any person or circumstance, is for any reason held to be invalid, such invalidity shall not affect
other provisions or applications of this Ordinance which can be given effect without the invalid
provision or application, and to this end the provisions of this Ordinance are declared to be
severable. The Town Council hereby declares that it would have passed this Ordinance and each
provision thereof, even though any one of the provisions might be declared unconstitutional or
invalid. As used in this Section, the term "provision" means and includes any part, division,
subdivision, section, subsection, sentence, clause or phrase; the term "application" means and
includes an application of an ordinance or any part thereof, whether considered or construed
alone or together with another ordinance or ordinances, or part thereof, of the Town.
Section 6. Effective Date. This Ordinance shall take effect seven days after public notice
following final passage in accordance with Section 6.4 of the Avon Home Rule Charter.
Section 7. Safety Clause. The Town Council hereby finds, determines and declares that this
Ordinance is promulgated under the general police power of the Town of Avon, that it is
promulgated for the health, safety and welfare of the public, and that this Ordinance is necessary
for the preservation of health and safety and for the protection of public convenience and welfare. •
The Town Council further determines that the Ordinance bears a rational relation to the proper
legislative object sought to be obtained.
Section 8. No Existing Violation Affected. Nothing in this Ordinance shall be construed to
release, extinguish, alter, modify, or change in whole or in part any penalty, liability or right or
affect any audit, suit, or proceeding pending in any court, or any rights acquired, or liability
incurred, or any cause or causes of action acquired or existing which may have been incurred or
obtained under any ordinance or provision hereby repealed or amended by this Ordinance. Any
such ordinance or provision thereof so amended, repealed, or superseded by this Ordinance shall
be treated and held as remaining in force for the purpose of sustaining any and all proper actions,
suits, proceedings and prosecutions, for the enforcement of such penalty, liability, or right, and
for the purpose of sustaining any judgment, decree or order which can or may be rendered,
entered, or made in such actions, suits or proceedings, or prosecutions imposing, inflicting, or
declaring such penalty or liability or enforcing such right, and shall be treated and held as
remaining in force for the purpose of sustaining any and all proceedings, actions, hearings, and
appeals pending before any court or administrative tribunal.
Section 9. Publication by Posting. The Town Clerk is ordered to publish this Ordinance by
posting notice of adoption of this Ordinance on final reading by title in at least three public places
within the Town and posting at the office of the Town Clerk, which notice shall contain a
statement that a copy of the ordinance in full is available for public inspection in the office of the
Town Clerk during normal business hours.
•
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 2 of 3
V1 9.22.10
• INTRODUCED, APPROVED, PASSED ON FIRST READING, ORDERED POSTED
AND REFERRED TO PUBLIC HEARING and setting such public hearing for October 12,
2010 at the Council Chambers of the Avon Municipal Building, located at One Lake Street,
Avon, Colorado, on September 28, 2010 and October 12, 2010
Ronald C. Wolfe, Mayor
Published by posting in at least three public places in Town and posting at the office of the Town
Clerk at least seven days prior to final action by the Town Council.
ATTEST:
APPROVED AS TO FORM:
Patty McKenny, Town Clerk Eric Heil, Town Attorney
• INTRODUCED, FINALLY APPROVED, AND PASSED ON SECOND READING, AND
ORDERED PUBLISHED BY POSTING on October 26, 2010.
•
Brian Sipes, Mayor Pro Tem
Published by posting by title in at least three public places in Town and posting by title at the
office of the Town Clerk.
ATTEST:
Patty McKenny, Town Clerk
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 4 of 3
V19.22.10
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
TOWN OF AVON •
NOXIOUS WEED MANAGEMENT PLAN
ADOPTED BY THE TOWN COUNCIL ACTING AS
THE LOCAL WEED ADVISORY BOARD
ON OCTOBER 12, 2010
The Town of Avon in accordance with "Colorado Noxious Weed Act ", C.R.S. §35 -5.5 -101 et seq.
hereby designates the following plants as Noxious Weeds:
Management Method #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Common Name:
Scientific Name:
Leafy Spurge
Euphorbia esula
Russian Knapweed
Acroptilon repens
Diffuse Knapweed
Centaurea diffusa
Spotted Knapweed
Centaurea maculosa
Canada Thistle
Cirsium arvense
Musk Thistle
Carduus nutans
Plumeless Thistle
Carduus acanthoides
Scotch Thistle
Onopordum acanthium
Houndstongue
Cynoglossum officinale
Whitetop /Hoary Cress
Cardaria draba
Yellow Toadflax
Linaria vulgaris
Oxeye Daisy
Chrysanthemum leucanthemum
Dalmatian Toadflax
Linaria dalmatica
Common Tansy
Tanacetum vulgare
Scentless Chamomile
Matricaria perforate
Salt Cedar
Tamarix chinensis
Yellow Sweet Clover
Melilotus officinalis
Black henbane
Hyoscyamus niger
Bull Thistle
Cirsium vulgare
Chinese clematis
Clematis orientalis
Eurasian watermilfoil
Myriophyllum spicatum
Perennial pepperweed
Lepidium latifolium
Russian -olive
Elaeagnus angusifolia
Spurred anoda
Anoda cristata
Sulfur cinquefoil
Potentilla recta
Venice mallow
Hibiscus trionum
The purpose of this Noxious Weed Management Plan is to adopt a list of noxious weeds for the
Town of Avon. The basis for this list is set forth in the "Colorado Noxious Weed Act" C.R.S. §35-
5.5 -101 et seq. Weeds which commonly occur in Avon and which are listed on the state's A, B, and
C list at the time of adoption are identified above. In addition, yellow sweet clover (Melilotus
officinalis) has been identified as noxious by the Town of Avon. Although this plant is not currently
listed on the state's list, it is identified as noxious by the town and included herein because it is very
invasive, detrimental to cattle, has been found to be problematic in Avon, and is expected to be
added to the state's noxious weed list.'
' This species is listed as invasive in 26 states including Colorado, Arizona, Texas, Wyoming, and Utah. See:
Town of Avon: Noxious Weed Management Plan
Page 1 of 14
812712010
•
•
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• It is expressly understood in this Plan that the above - referenced list shall be inclusive of all "List A"
species of noxious weeds to the extent they are found within the Town of Avon and identified for
mandatory eradication by the State of Colorado. It is also expressly understood that any and all
"List B" species of noxious weeds not currently listed above, but later found within the Town of
Avon and identified by the state for mandatory eradication pursuant to state regulation 8 CCR 1203-
19, shall be incorporated into this plan and that no amendment hereto shall be necessary prior to
taking enforcement action for the eradication of said species.
The Town of Avon may annually review and update this list of noxious weeds pursuant to state
statute, or sooner if necessary.
I. Introduction
The noxious weeds that have currently invaded our community have become a threat to the
economic and environmental value of land in the Town of Avon. These weeds are not
indigenous to this county and have no natural predators or diseases to keep them in check.
They are rapidly displacing desirable vegetation causing a loss of productive wildlife grazing
and recreational resources. An integrated noxious weed management plan must include best
practice strategies along with the Federal, State of Colorado, Town of Avon and Private land
owners, working together to meet the challenges we now face in our state.
II. Goals of this plan
• Adopting and implementing the Colorado Noxious Weed Act as they apply to the Town
of Avon. The Town of Avon Noxious Weed Regulations as it pertains to noxious weeds
will automatically update along with all future revisions and amendments to the
• Colorado Noxious Weed Act.
• Education of the public and private landowners concerning weed management issues
facing our community.
• Work with the Federal, State, County, and private landowners to implement "Best
Management Practices. "
• Identify, inventory and map out noxious weeds currently in our community and use as a
means to monitor our effectiveness and as a tool for future work plans.
I1I. Weed Management Methods
The Colorado Noxious Weed Act provides that integrated methods must be utilized in the
management of weeds. Integrated methods include but are not limited to: Cultural, Chemical,
Biological and Mechanical management. For proper control of a particular weed species, it
may be necessary to utilize more than one method. The following general comments regard
control methodology apply to all listed or otherwise identified noxious weeds, unless
otherwise specifically excluded in the detailed management plan listed below for a particular
plant species:
• Cultural — those methodologies or practices conducted to favor the growth of
desirable plants over undesirable plants. Including but not limited to: maintaining an
htti): / /www.na.fs.fed.us /fhp /invasive plants /weeds /vellow sweetclover.pdf
• Whitson, T.D. (ed.) et al. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative
Extension Services, University of Wyoming. Laramie, Wyoming.
United States Department of Agriculture, Accessed online on April 8, 2010 at
http://plants.usda.gov/eava/profile?svmbol=MEOF.
Town of Avon: Noxious Weed Management Plan
Page 2 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting local Designation of Noxious Weeds
optimum fertility and plant moisture status in an area, and planting species most •
suited to an area. (e.g., Grazing, Revegetation for wildlife)
• Erosion Control — Healthy plant revegetation of all disturbed sites with acceptable
grasses, trees, and other plantings, with a 2 year warranty and extensive weed control
during the re- growth period.
• Chemical — the use of herbicides or plant growth regulators to disrupt the growth of
undesirable plants. (e.g., Herbicides)
• Biological — the use of organisms to disrupt the growth of undesirable plants. (e.g.,
insects, bacteria, pathogens, goats)
• Mechanical — practices that physically disrupt plant growth including but not limited
to: tilling, mowing, burning, cutting, mulching, hand pulling, and hoeing. Tilling,
mowing, mulching, and hoeing are generally only effective if done to plants prior to
the flowering stage. After this stage the seeds have formed and these plants must be
completely removed from the property by cutting or hand- pulling as part of the
mitigation effort Cut plants which include buds, flowers, or seed pods should be
placed in clear plastic bags, the bags labeled "noxious weeds ", and landfill disposed.
Landfill disposal should be done through a licensed landscape maintenance
contractor or by direct deposit in the landfill. Unless otherwise recommended below,
no removed weed material which includes buds, flowers, or seed pods should be
burned, composted, or heaped, or otherwise left exposed.
Note that personal protective equipment (PPE) should be worn when conducting weed
mitigation. This may include gloves, long sleeve shorts, full length pants, safety boots, and •
safety glasses. Mitigation work should be done carefully because some of the weeds and
herbicides can cause eye and/or skin irritation.
IV. Managed Species Information
1. Leafy spurge - (Euphorbia esula) a perennial that spreads by seed and creeping rootstocks.
An extensive root system with vast nutrient reserves makes this plant extremely difficult to
control. Management Methods:
a) Cultural: seeding perennial grasses can be an effective management tool. Early emerging
plant species that utilize early season moisture such as smooth brone (Bromus inermis) or
crested wheat grass have reduced leafy spurge density and limited the spread and
establishment of new infestations. Alfalfa can also be a good competitor with leafy
spurge.
b) Chemical: Contact a licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: grazing with sheep or goats can stress leafy spurge making it more
susceptible to other control methods. Apthona flava and Apthona nigriscutis are two
species of flea beetles that have been introduced to attack leafy spurge. Adults feed on
foliage during summer and lay eggs at the base of spurge plants. The larvae tunnel the
soil and mine the roots as well as the fine root hairs. These insects along will not control
leafy spurge but they can weaken the plant making it more susceptible to herbicide
treatments or other control methods.
d) Mechanical: mechanical methods have not been proven to be an effective management
tool on this plant. •
Comments: A complex of insects, grazing, plant disease and chemical methods will be
necessary to stress the plant sufficiently to attain acceptable control.
Town of Avon: Noxious Weed Management Plan
Page 3 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• 2. Russian Knapweed - (Acroptilon repens) A creeping perennial weed which once
established, becomes extremely difficult to control. In heavy infestations few plants can
grow in competition. Management Methods:
a) Cultural: dry range seeded with Crested wheatgrass can cause stress in knapweed by
using up moisture for spring growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: a leaf & stem gall- forming nematode (Subanguina peridus) has been released
in the U.S. This nematode had shown limited success in controlling Russian knapweed
d) Mechanical: due to the extensive energy reserves in the root system, removal of top
growth alone will not provide adequate control of Russian knapweed. In fact recent
studies have shown that mowing increases Russian knapweed density and stimulates
growth.
3. Diffuse Knapweed - (Centaurea diffusa) is a biennial or short lived perennial which has
become one of the most damaging rangeland weeds in the Northwest inter - mountain area.
Management Methods:
a) Cultural: Seeding of Crested wheatgrass can inhibit the spread of diffuse knapweed in
dry climates
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies (Uphora affins and Uphora quadrifaciata)
• attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
4. Spotted Knapweed - (Centaurea maculosa) is a biennial or short lived perennial that
greatly reduces the range's carrying capacity for both livestock and wildlife. Management
Methods:
a) Cultural: Good grazing management is one of the best defenses against the spread of
knapweeds on the range and pasture lands. Proper stocking rates, good livestock
distribution and correct timing and deferment of grazing are essential to the maintenance
of a healthy range or pasture environment.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies (Uphora affins and Uphora quadrifaciata)
attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
5. Canada Thistle — (Cirsium arvense ) A perennial weed with an extensive root system,
• Canada Thistle reproduces both by seed and by vegetation buds on the roots. This requires a
much more extensive management plan than the biennial thistles. Management Methods:
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a) Cultural: Cultivation may increase the number of plants by spreading the roots to new •
areas where they may become established. Competitive crops, especially alfalfa and
forage grasses may be used to control Canada thistle infestations. Choose aggressive
grass with early season vigor to plant in areas where Canada thistle is present.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Ceutorhynchus litura is a stem weevil whose larvae mine tissues of the leaf,
root crown and root. Outward signs of damage by this larvae are not readily apparent but
secondary damage is caused by other organisms which enter the plants through exit holes
made by the larvae. Urophora cardui is a stem gall fly whose larvae cause galls to form
on the stem of Canada thistle plants. The galls reduce the plant's vigor making it less
able to compete with other plants or to resist pathogens or attacks by other insects. It is
essential that both of these insects be combined with other methods of control for
adequate management of Canada thistle.
d) Mechanical: Mowing can be an effective tool when combined with herbicide treatment.
Mowing alone is not effective unless conducted at two week intervals over several
growing seasons. Mowing should always be combined with cultural and chemical
control.
6. Musk Thistle — (Carduus nutans) is a biennial weed. Biennial weeds are best controlled in
their first year of growth. Very commonly found noxious weed in Eagle County.
Management Methods:
a) Cultural: The best way to prevent or reduce the amount of biennial thistle is to manage
areas that are susceptible to invasion •
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Rhinocyllus conicus is a flower head weevil which is widely distributed in
Eagle County. This weevil consumes most of the seeds in the terminal flower heads, but
has no effect on buds which form later in the season. The conicus weevil can be an
effective control method only if it is combined with chemical mechanical controls.
Trichosirocalus horridus is a crown weevil which feeds on the growing tip of the thistle
rosette. This weevil has been released on numerous occasions in Eagle County but has
not yet become established. Due to the very nature of the predator prey cycle the bio
control listed above will not completely eliminate the thistle.
d) Mechanical: Since these thistles are biennials and do not resprout, they are easily killed
by tillage or any method that severs the taproot below the crown of the plant. If dug or
cut after seed heads have formed the plants should be burned or otherwise destroyed so
the seeds will not mature. Mowing is effective only if done when flowers first open.
Comments: A second mowing may be necessary because the plants may recover and
produce viable seed later in the growing season.
7. Plumeless Thistle — (Carduus acanthoides). See description and management method for
the Musk Thistle ( #6 above).
8. Scotch Thistle — (Onopordum acanthium). See description and management method for the
Musk Thistle ( #6 above)
9. Houndstongue — (Cynoglossum officinale) is a biennial weed which is toxic to horses and
cattle. The seed is contained in pods, which are covered with barbs enabling them to stick to •
clothing or animal hair, and thus readily transported. Management Methods:
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
0 a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No biological controls are available at this time.
d) Mechanical: Severing the taproot below the crown will control Houndstongue. After
cutting, the plants should be burned or removed if they are in bloom to prevent seed
formation.
10. Hoary Cress Whitetop — (Cardaria draba ) is a perennial plant, which is very competitive
with native vegetation. Its early seeding habits make it difficult to effect control in a timely
manner. Management Methods:
a) Cultural: The effectiveness of mowing or cultivation will be increased if perennial
grasses or alfalfa are seeded as competitor species. Promote healthy grass in rangeland or
pastures by using proper irrigation and fertilization techniques.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No insects are known to be effective for controlling this weed.
d) Mechanical: No scientific data is available on mechanical control for this species.
Mowing just prior to seed set may reduce overall seed production, but must repeated
• several times during the growing season.
11. Yellow Toadflax - (Linaria vulgaris) This deep- rooted perennial plant is an aggressive
invader of rangeland, pasture and waste areas. Once established on a site it is one of the most
difficult noxious weeds to control. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the amount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a year
for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
12. Dalmation Toadflax — (Linaria dalmatica) An introduced perennial with a creeping root
system. This plant may suppress desirable grasses even in well managed rangeland or
pastures. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
• b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting local Designation of Noxious Weeds
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general •
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the amount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a year
for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
13. Oxeye Daisy — (Chrysanthemum leucanthemum) A member of the sunflower family is an
erect perennial plant with white ray and yellow disk flowers which bloom from June through
August. A native of Eurasia, this aggressive plant has escaped cultivation and become a
troublesome weed in the Intermountain West.
Management Methods:
a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known
d) Mechanical: Hand pulling or digging before seed head production can used to effectively
control small infestations. However, for this method to be successful it is important to
remove as much of the underground part as possible. •
14. Scentless Chamomile — (Marticaria perforata) An escaped ornamental plant, this annual
has become widely established in the eastern part of Eagle County and is a threat to native
plant communities. Management methods:
a) Cultural: Learn to identify the plant and physically remove them when they first appear.
Seed competitive cool season grasses that out compete this plant at its early stage of
growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No known biological controls
d) Mechanical: Since it is an annual plant, chamomile can be controlled by hand pulling,
cultivation, or any type of physical disturbance.
15. Common Tansy - (Tanacetum vulgare) An escaped ornamental, is a perennial plant, from 1
'/2 feet to 6 feet tall with showy button -like flowers. Tansy is a member of the sunflower
family and has become widely established on the western slope of Colorado. Flowering
typically occurs from July to September. Tansy reproduces by both seed and creeping
rootstock. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known •
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting local Designation of Noxious Weeds
0 d) Mechanical: can be mowed before flowering and seed set to eliminate seed production.
This method may have to be repeated to eliminate regrowth from the rootstock.
16. Salt Cedar (Tamarix chinensis) is a evergreen shrub or small tree which grows near water
and hydric soils and reaches a height of 5 to 20 feet tall. The leaves are small, scale -like and
bluish -green in color. Tiny pink to white colored flowers have five petals and grow on
slender racemes. Salt Cedar reproduces by seed. This is an aggressive plant that
outcompetes native vegetation and consumes a lot of water. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Salt Cedar Leaf Beetle (Diorhabda elongate) larvae and adults feed on
foliage and can cause plant death if defoliation is consistent. This beetle is commercially
available for distribution.
d) Mechanical: A bulldozer, chainsaw, or prescribed fire can be used in conjuction with
follow -up herbicide treatment for returning sprouts.
17. Yellow Sweet Clover (Melilotus officinalis) is an annual or biennial legume which grows
from 2 to 6 feet tall. It has small yellow to white flowers in a multiflowered terminal and
along auxillary racemes, serrated trifoliate leaves, somewhat resembles alfalfa. It is not
native to Colorado and appears on disturbed sites. It is a drought - tolerant plant. Although
useful for honey producers, it causes bloat in cattle and anticoagulation of blood. The plant
• degrades native grasslands and reduces biodiversity by competing for nutrients and by
covering and shading native sun - loving plant species. It reproduces by seed, producing as
many as 100,000 seeds per plant; seeds may remain viable for up to 20 years. Management
Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Sitona cylindricollis, the sweetclover weevil, may severely damage the plant.
Adults of the insect feed on the foliage and larvae feed on the roots of the plant. A
sweetclover root borer, Walshia miscecolrella, is a native insect that may damage
sweetclover plants on rare occasions. An ash -gray blister beetle, Epicauta fabricii, a
striped blister beetle, Epicauta vittata, and a margined blister beetle, Epicauta pestifera,
have also been found feeding on the plant. Yellow sweetclover is palatable by livestock
- within the risks mentioned above - and plant infestations may be reduced if heavily
grazed.
d) Mechanical: Hand pull early and when the soil is moist. Completely remove all plants
containing seeds. Burning has had variable results, including increasing germination,
and is therefore not recommended.
18. Black henbane (Hyoscyamus niger) was introduced from Europe as an ornamental and
medicinal herb; it is now found across on the western slope of Colorado. A mature plant
reaches 1 to 3 feet in height with foliage that has a fowl odor. Fruits are approximately I inch
• long with 5 lobes. It is often found in disturbed open spaces, roadsides, fields, waste places
and abandoned gardens. It grows in most soil types but likes sandy or well drained loam
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
soils. The seed viability or longevity is considered to be 1 to 5 years. All parts of Black •
henbane are poisonous to both livestock and humans when ingested. The plant is a strong
competitor for moisture and nutrients and produces a persistent litter effecting germination
and growth of native plants. Management Methods:
a) Cultural: Cultural controls are possible in theory, but are very time consuming and
expensive. Complete removal of any seedlings or newly established plants by continual
hand pulling is also possible.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
d) Mechanical: Hand pull or dig from moist soil, so the entire tap root system can be
removed. Tillage will control henbane, but is usually not recommended due to the land it
occupies: rangeland, roadsides and pastures. Be sure to bag specimens carefully if
removed during or after flowering.
Comments: A preventable measure is to guard against disturbance and overgrazing.
Controlling plants in the spring or early summer prior to seed production is most effective,
follow -up treatments are recommended to pick up missed or late bolting plants.
19. Bull Thistle (Cirsium vulgare) is a biennial forb that was accidently introduced to North
America as a seed contaminant. In Colorado, Bull thistles are the only species that are
prickly hairy on the top and are cottony -hairy on the undersides of the leaves. Mature plants
can produce up to 4,000 seeds per plant. Commonly seen in areas such as pastures,
overgrazed rangeland, roadsides, and logged areas. It is not especially shade tolerant. •
Bull thistle is an aggressive weed and is often a transient species, appearing in recent clear
cuts or disturbed areas and becoming a dominant species for several years. It has been
reported to cause hay fever in some individuals and is often confused with musk thistle. Bull
thistle infestations have been reported to occur in nearly all Colorado counties west of the
continental divide, in the Upper Arkansas Watershed, and in pockets on the plains. Heavy
infestations can reduce livestock forage. The presence of bull thistle in hay decreases the
forage value and lowers the market price. Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
Contact your local Natural Resources Conservation Service for seed mix
recommendations. Maintain healthy pastures and prevent bare spots caused by
overgrazing.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Urophora stylata, a fly predator, is used to help control this thistle. The
female fly lays eggs in the seed head of the thistle. The maggot then consumes the seed
in the flower. This species has overwintered in Colorado but the limited numbers will not
allow for general redistribution. For more information, contact the Palisade Insectary of
the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Because biennial thistles do not reproduce from their roots, any mechanical
or physical method that severs the root below the soil surface will kill the weed. It is
necessary to revegetate the site with desirable plants. Tillage, hoeing, or even hand- •
pulling should be successful (not on rangeland), providing it is done before the
reproductive growth stages.
Town of Avon: Noxious Weed Management Plan
Page 9 of 14
8127/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
is Comments: The key to effective control is maintaining healthy pastures and rangeland,
guarding against disturbance or overuse, and to limit seed production by collecting and
destroying plants with seeds. Chemical control is most effective when plants are in rosette
stage, spring or early fall. Mechanical controls can be used to eliminate small patches or
plants in a later growth stages.
20. Chinese clematis (Clematis orientalis) is an herbaceous to woody vined perennial which
can climb up to 12 feet. It is native to Eurasia. It has solitary flowers with four yellow
sepals (flowering from August to September) which produces numerous feathery, long- tailed
fruits which are conspicuous all winter. This plant prefers roadsides, riparian corridors, and
rocky slopes although it is sometimes found in open woods. This species can cause death to
young trees and brush. It outcompetes native shrubby and herbaceous species. Plants will
completely cover rock walls, trees, bushes and fences. The juice of freshly crushed leaves
and stems have blister causing agents. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
d) Mechanical: Handpull or dig when soil is moist. Make certain to pull all the roots. Bag
specimens carefully so as to not scatter seeds if flowering.
21. Eurasian watermilfoil (Myriophyllum spicatum) is an aquatic weed with feathery
underwater foliage that is native to Northern Europe and Asia. Eurasian watermilfoil spreads
most commonly by stem fragmentation, runners, and from free floating plants which
• eventually root. It can also spread by seed. The plant is typically submersed with stems to 4
m long. Habitats for Eurasian watermilfoil include: ponds, lakes, rivers, streams, canals, and
ditches. Usually the plant inhabits slow moving water areas but can infest fast moving
water, such as streams and rivers. Eurasian watermilfoil is very invasive. The plant forms
very dense mats of vegetation on the surface of the water. Mats interfere with recreational
activities (e.g. swimming, fishing, skiing, boating, etc.), create mosquito habitat, reduce
native vegetation, and clog intake structures in power generation, irrigation systems, and
potable water intakes. Management Methods:
a) Cultural: Prevention of Eurasian watermilfoil is the best cultural control. Other methods
of cultural controls are possible in theory, but are very time consuming and expensive.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: There is biological control available for Eurasian watermilfoil, but it is not
yet approved for use in Colorado. For more information, contact the Palisade Insectary
of the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Hand pulling, raking, harvesting are effective at reducing current abundance
of plants and is useful to clear channels or maintain access. However; it is not a very
good long term control and is very expensive, labor intensive, and several removals are
needed each year.
Comments: The key to effective control is typically prevention of uncontrolled
monocultures . Chemical and mechanical controls are well developed, but provide short to
medium -term control.
• 22. Perennial pepperweed (Lepidium latifolium) is an extremely invasive perennial forb
introduced from Europe and Asia as a containment in sugar beet seed. Pepperweed
reproduces both by seed and vegetatively by roots and shoots. Pepperweed has tiny white
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
spoon- shaped petals on the flowers. It readily invades disturbed and bareground areas. •
Pepperweed is a serious threat because it alters ecosystems by acting as a "salt pump"
absorbing salts from deep in the soil. The plant then excretes the salt through the leaves and
deposits it on the surface soil. Since most desirable plants do not tolerate high saline
concentrated soils, the entire plant composition and diversity of the area changes. Large
monocultures and dense litter layers prevent native plants from regenerating. Pepperweed
displaces native plants and wildlife habitats, reduces food quality for wildlife and reduces
agricultural and pasture production. Management Methods:
a) Cultural: Prolonged spring flooding of new growth will kill pepperweed. Grazing is not
recommended because the plant may be toxic. Reestablishing the native or desired plants
can take years, so repeat plantings must be repeated, but it can aid in controlling
populations.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Biological control is not a viable option because 11 other species of native
Lepidium are on the Endangered species list, and the risk to these species as well as
agricultural species is too great.
d) Mechanical: Due to the deep, brittle root, most mechanical methods are not recommend,
and can actually propagate, spread and increase the density of pepperweed. Hand pulling
can also bring seeds to the soil surface, and spread pieces of root, which will sprout.
However, spring mowing combined with chemical treatments can be effective.
Comments: It is important to prevent establishment of large populations via early detection
and removal. Planting desirable and competing grasses and forbs is recommended
Herbicide treatments are a good option if used during the bud to flowering stage of the plant. •
23. Russian -olive (Elaeagnus angusifolia) is a perennial tree or shrub that is native in Europe
and Asia. The plant has olive - shaped fruits, silver color at first then becoming yellow -red
when mature. Russian olive can reproduce by seed or root suckers. Seeds can remain viable
for up to 3 years. The plants extensive root system, sprouts root suckers frequently. The
lower surface is silvery white with dense scales, while the upper surface of the leaf is light
green in color. Previously thought to be a beneficial windbreak tree, it since has been
deemed detrimental to the environment because it competes native vegetation, interferes
with natural plant succession and nutrient cycling, and taxes water reserves. Russian olive
can grow in a variety of conditions. Although Russian -olive provides a plentiful source of
edible fruits for birds, ecologists have found that bird species richness is actually higher in
riparian areas dominated by native vegetation. The key to effective control of Russian olive
is preventing establishment of the trees or shrubs. The state of Colorado mandates control
state -wide and requires eradication in most riparian areas. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
Biological: Tubercularia canker overwinters on infected stems and spreads via rain -
splash, animals, or pruning implements to open wounds in the bark. Infected tissue
becomes discolored or sunken. Entire stems may be girdled and killed, and the disease
can deform or kill stressed plants over time. For more information, contact the Colorado
Department of Agriculture's Insectary in Palisade, Colorado at 970 - 464 -7916.
d) Mechanical: Cut down the tree. Mowing with a brush type mower, followed by removal •
of cut material, is another options for smaller shoot - hedges. Stump sprouting commonly
occurs after cutting down the tree, and excavation of the entire stump can trigger root
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• sprouting. Burning is practical when conditions support a long hot fire and most effective
in summer or early fall (burn permit required, call the Eagle River Fire Protection
District at 748 - 9665).
Comments: As a water conservation measure, Avon requires elimination of existing Russian
Olive trees from water courses but allows continued stand on higher ground where property
owners commit to control measures. Avon's weed management requirements on this species
are as follows:
• Removal is required if the tree is within 25 feet of the high water mark of a permanent
creek, stream, river; or within 25 feet of the top or rim of an irrigation canal, ditch or
ephemeral water course.
• Removal or control is allowed if tree is outside of water course boundaries.
A written commitment by the property owner or property manager for controlling the spread
of this species must be on -file to remain in compliance with Avon's Noxious Weed
Ordinance. Contact Avon Public Works, 500 Swift Gulch Rd, Avon 81620, call 970 -748-
4100 or by e-mail at weeds @avon.org.
Replacing with native trees is important once Russian olive has been removed, and is
required when the tree had previously been part of approved site landscaping. Contact Avon
Community Development at 970 - 748 -4030 for information about modifying your
landscaping plan.
24. Spurred anoda ( Anoda cristata) is a summer annual forb with a low growing, spreading
profile. The seedlings have one round and one heart - shaped cotyledon with hairs along the
• margins of the leaves. The flowers appear August through November and are light blue to
lavender in color. Habitats include: ditches, within crops, along roadsides, gardens, waste
areas and disturbed sites. Spurred anoda is considered an agricultural weed and is found
mainly in agricultural crops (corn, cotton, beans, etc.). Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
b) Chemical: N/A
c) Biological: N/A
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully as not to spread seeds.
Comments: Preventing seed production is key. Small patches can be controlled by hand
pulling or hoeing
25. Sulfur cinquefoil (Potentilla recta) is a perennial forb that is native to Eurasia. Leafstalks
have conspicuous perpendicular hairs and leaves appear green on the underside; plants can
grow 28 inches in height. The flowers are pale yellow. Sulfur cinquefoil grows on dry
sandy, gravelly, and rocky soils. Bareground is prime habitat for weed invasions. It is important
to properly identify sulfur cinquefoil, since it resembles the native cinquefoils. Management
Methods:
a) Cultural: Increasing the competitiveness of native species can assist in preventing
establishment of Sulfur cinquefoil. Contact your local Natural Resources Conservation
• Service for seed mix recommendations.
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
b) Chemical: Contact licensed commercial applicator for specific recommendations for •
herbicide use.
c) Biological: Biocontrol species have been used in trials, since Sulfur cinquefoil is similar
to strawberries though, the insects used are considered pests. For more information,
contact the Colorado Department of Agriculture's Insectary in Palisade, Colorado at 970-
464 -7916.
d) Mechanical: Mowing is not effective, as new shoots will replace the cut steams. Hand
dig or pull when soil is moist is effective on small infestations. Be sure to dig up as much
of the root system as possible, especially since root fragments can produce new plants.
Comments: Hand pulling or digging when infestations are small and the soil is moist
combined with use of herbicides has proven to be effective.
26. Venice mallow (Hibiscus trionum) is a summer annual forb that has a spreading profile and
is native to Europe. The seeds are dark brown and can remain viable for 50 years. The
cotyledons are round with hairy petioles. The stems are erect and hairy, growing to about 18
inches tall. The first true leaves have toothed margins and are alternate. Flowers are a light
sulfur to yellow color with a red to purple center which only last a couple of hours. Venice
mallow is an agricultural weed. Management Methods:
a) Cultural: Outcompeting Venice mallow, is difficult with native grasses and forbs, since
Venice mallow likes agricultural crop areas. But, contact your local Natural Resources
Conservation Service for seed mix recommendations that may help in rangeland areas.
Bareground is prime habitat for weed invasions.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use. •
c) Biological: N/A
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully so as not to spread seeds.
Comments: Best control is to prevent establishment of the plant and seed production with
early detection and physical removal. Herbicide treatments are another control option.
Multiple applications or a pre- emergence application will be most effective. When soils are
moist, hand pulling or digging is effective provided that you bag the removed plants.
V. Acknowledgements
The Town of Avon sincerely appreciates the great work done by botanists, scientists, and
others at the State of Colorado, Department of Agriculture and at the Colorado State
University Extension offices. These resources were the primary source of all of the technical
information contained in this plan. State and CSU staff reviewed this document prior to the
Town's 2010 adoption.
•
Town of Avon: Noxious Weed Management Plan
Page 13 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
isState of Colorado
•
1�
Department of Agriculture
Noxious Weed Program
(303) 239 -4100
http: / /www.colorado.gov /cs /Satellite/ Agriculture- Main/CDAG/1174084048733
Colorado State University Extension
Eagle County Office
P.O. Box 239
441 Broadway
Eagle CO 81631
(970) 325 -8630
http: / /www.eaglecounty.us /csu/
For more information, including color photos of all the species listed here, please
contact either of the above resources.
If you have general questions on noxious weeds or have received a noxious weed
violation notice, please call Avon Public Works at (970) 748 -4100.
Town of Avon: Noxious Weed Management Plan
Page 14 of 14
8/27/2010
•
Memo
To: Honorable Mayor and Town Council
Thru: Larry Brooks, Town Manager
Legal Review: Eric Heil, Town Attorney04 -�
From: Jennifer Strehler, Director of Public Works and TransportatioQQ��
Date: September 24, 2010
Re: Ordinance No. 10 -18 Adopting Local Designation of Noxious
Weeds
Summary:
Town Council originally passed an ordinance in April 2010 amending the town code
•regarding noxious and nuisance weeds. Approval of the ordinance is now needed to
fulfill a state requirement regarding a 30 -day public notice period. Public notice for
this September 28th hearing was posted on August 27, 2010 at the Town's customary
public notice locations. Also the associated noxious weed management plan has been
amended to add several weeds designated by the state for control or eradication in
Eagle County which were previously not included. A motion approving of the updated
management plan is also needed.
Previous Council Actions:
On April 13, 2010, Town Council discussed proposed Ordinance 10 -06, "An Ordinance
Enacting Noxious Weed Control Regulations" which revised § §8.24.046 of the Avon
Municipal Code entitled 'Undesirable Plants" (1992) and also § §8.24.045 entitled
"Weeds" (1983). It was approved upon first reading but with the request that the
originally proposed language regarding non - noxious but nuisance weeds and grass
mow heights be removed. Staff made these changes and submitted a revised
ordinance for consideration on April 27, 2010.
On April 27, 2010, a public hearing was held regarding Ordinance 10 -06. The Town
Council approved Ordinance 10 -06 upon second reading. The new ordinance language
can be found in §8.36 of the Avon Municipal Code.
Town received communications disputing the Town's legal authority to enforce locally
designated noxious weeds. Although the Town did post notice of Ordinance No. 10 -06
• Adopting Noxious Weed Regulations 30 days prior to the first reading of Ordinance No.
10 -06; the Town Attorney has recommended that the Town re- notice the local
designation of noxious weeds.
Page I of 4 Council Memo
In
Background:
The Colorado Noxious Weed Act §§ 35- 5.5.101 through 119 (CRS 2003) requires local •
governments to rules set forth in 8 CCR 1206 -2 and in the Act to control the spread of
noxious weeds. The state requires counties, cities, and towns to adopt a specific
noxious weed management plan. Avon is compliant this regard, with the Town
Council acting as the local Weed Management Advisory Commission.
A copy of the public notice posted for this hearing is attached. This notice was posted
on August 27, 2010 at the Town's customary public notice locations.
Discussion:
Avon's Noxious Weed Management Plan includes all of the state's List A species plus
the species listed below. Species ID # 18 -26 have been added to Avon's plan since
the previously approved April version. These were added because they are identified
for control or eradication in Eagle County in 8 CCR 1206 -2. In the event the state
adds another species to List A or to List B with an explicit requirement for eradication
in Eagle County, Avon's management plan "automatically updates" to include such
added species.
Management Method #
Common Name:
Scientific Name:
1
Leafy Spurge
Euphorbia esula
2
Russian Knapweed
Acroptilon repens
3
Diffuse Knapweed
Centaurea diffusa
4
5
Spotted Knapweed
Canada Thistle
Centaurea maculosa
Cirsium arvense
•
6
Musk Thistle
Carduus nutans
7
Plumeless Thistle
Carduus acanthoides
8
Scotch Thistle
Onopordum acanthium
9
Houndstongue
Cynoglossum officinale
10
Whitetop /Hoary Cress
Cardaria draba
11
Yellow Toadflax
Linaria vulgaris
12
Oxeye Daisy
Chrysanthemum leucanthemum
13
Dalmatian Toadflax
Linaria dalmatica
14
Common Tansy
Tanacetum vulgare
15
Scentless Chamomile
Matricaria perforate
16
Salt Cedar
Tamarix chinensis
17
Yellow Sweet Clover
Melilotus officinalis
18
Black henbane
Hyoscyomus niger
19
Bull Thistle
Cirsium vulgare
20
Chinese clematis
Clematis orientalis
21
Eurasian watermilfoil
Myriophyllum spicatum
22
Perennial pepperweed
Lepidium latifolium
23
Russian -olive
Elaeagnus angusifolia
24
Spurred anoda
Anoda cristata
25
Sulfur cinquefoil
Potentilla recta
26
Venice mallow
Hibiscus trionum
•
At a minimum the state requires the local authority to eradicate all of the List A
q Y
Page 2 of 4 Council Memo
species and either eradicate or control all List B species. Some List B species are
• more or less of a threat in a particular geographic area, as described in 8 CCR 1206 -2.
It is important to understand that the state's rules and regulations regarding noxious
weeds and best management practices are still evolving. For example, at the time of
adoption of 8 CCR 1206 -2, the state did not have a formal management approach to
all List B species (e.g., Canada thistle, Russian Olive). Since that time, federal, state,
and county best management practices have been developed. In using the term
"control," the state rules may mean either "elimination of all populations" or
"suppression ", with the distinction depending on the specific plant and a specific
geographic area.
Local home rule authorities are legally empowered to include additional species in the
locally managed noxious weed list. Local governments are not limited by state law to
regulate only those plants on the state's List A, B or C. Also, Local governments do
not need to wait for the state to publish their plan for management of a particular
species in order to take local action.
Yellow Sweet Clover ( #17 in list above) is the only species on Avon's designated
noxious weed list that is not currently included on any of the states A, B or C list. This
plant is highly prevalent on many disturbed or poorly re- vegetated sites in Avon.
Town staff originally included this plant in the April list because technical sources
report it to be invasive, produce over 100,0000 seeds per plant, outcompete native
vegetation, cause anti - coagulation properties in the blood of grazing animals, and be
•very high in pollen.' Eagle County's Weed Coordinator, Tim Girard, commented that
this plant has been used in re- vegetation mixes and can be beneficial for bee keepers.
While Avon staff recognizes this, they recommend continued inclusion of this species
in Avon's noxious weed list due to all of its other negative attributes.
Financial Implications:
No change.
Recommendation:
Staff recommends passage of Ordinance 10 -06 and approval of the updated Noxious
Weed Management Plan.
Motion:
"I move to approve Ordinance 10 -18, Series 2010, Adopting Local Designation of
Noxious Weeds."
Town Manager Comments:
Q%
This species is listed as invasive in 26 states including Colorado, Arizona, Texas, Wyoming, and Utah. See:
U.S. Forest Service. Weed of the Week: Yellow Sweetclover. Accessed February 2009:
http: / /www.na,fs.fed,us /fhp /invasive plants /weeds /yellow sweetclover.pdf
• Whitson, T.D. (ed.) et al. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative
Extension Services, University of Wyoming. Laramie, Wyoming.
United States Department of Agriculture, Accessed online on April 8, 2010 at
httr):Hplants.usda.gov /iava /profile ?symbol =MEOF.
Page 3 of 4 Council Memo
Exhibits: •
• Copy of Notice
• Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• Exhibit A: Noxious Weed Management Plan to Ordinance No. 10 -18
•
•
Page 4 of 4 Council Memo
NOTICE OF PUBLIC HEARING REGARDING DECLARATION OF ADDITIONAL
• NOXIOUS WEEDS
Notice is hereby given, that the Town Council of the Town of Avon, shall conduct a public hearing
at the Avon Town Hall, located at One Lake Street, Avon, Colorado, on September 28`h, 2010, at
5:30 p.m. or as soon thereafter as possible, regarding the designation of additional noxious weeds.
Written comments may be e- mailed to Avon Public Works weeds@avon.org or may be mailed to
Town of Avon, P.O. Box 975, Avon, CO 81620. Written comments received by September 22,
2010 shall be included in the Town Council materials for their review and consideration. Copies of
the Town of Avon Noxious Weed Management Plan may be obtained from the Town Hall during
normal business hours or by Gary Padilla, Avon Road and Bridge Superintendent, Avon Public
Works (970) 748 -4100 or via e -mail at weeds@avon.org.
The Town of Avon has adopted by reference the List A species as designated by the State of
Colorado, Department of Agriculture, in 8 CCR 1206 -2. The authority for local declaration of
noxious weeds is pursuant to the Colorado Noxious Weed Act, Article 5.5, Title 35, Colorado
Revised Statute, Ordinance No. 10 -06 AN ORDINANCE ENACTING NOXIOUS WEED
CONTROL REGULATIONS, and by the Town of Avon's home rule authority.
The declaration of additional noxious weeds includes:
Black henbane (Hyoscyamus niger)
• Bull Thistle (Cirsium vulgare)
Canada thistle (Cirsium arvense)
Chinese clematis (Clematis orientalis)
Common tansy (Tanacetum vulgare)
Dalmatian toadflax, broad - leaved (Linaria dalmatica)
Diffuse knapweed (Centaurea diffusa)
Eurasian watermilfoil (Myriophyllum spicatum)
Hoary cress (Cardaria draba)
Houndstongue (Cynoglossum officinale)
Leafy spurge (Euphorbia esula)
Musk thistle (Carduus nutans)
Oxeye daisy (Chrysanthemum leucanthemum)
Perennial pepperweed (Lepidium latifolium)
Plumeless thistle (Carduus acanthoides)
Russian knapweed (Centaurea repens)
Russian-olive (Elaeagnus angusifolia)
Salt cedar (Tamarix chinensis, T.parviflora, and T. ramosissima)
Scentless chamomile (Matricaria perforata)
Scotch thistle (Onopordum acanthium)
Spotted knapweed (Centaurea maculosa)
Spurred anoda (Anoda cristata)
Sulfur cinquefoil (Potentilla recta)
• Venice mallow (Hibiscus trionum)
Yellow sweet clover (Melilotus officinalis)
Yellow toadflax (Linaria vulgaris)
Copy of Notice
TOWN OF AVON, COLORADO
ORDINANCE 10 -18 •
SERIES OF 2010
AN ORDINANCE ADOPTING LOCAL DESIGNATION OF NOXIOUS WEEDS
WHEREAS, the Town of Avon ( "Town ") is a home rule authority municipal corporation
and body politic organized under the laws of the State of Colorado and possessing the maximum
powers, authority and privileges to which it is entitled under Colorado law; and
WHEREAS, the Town Council is authorized to declare nuisances, establish fines and
penalties, and require abatement of public nuisances pursuant to its home rule authority and
pursuant to Colorado Revised Statute §31- 15- 401(1)(c); and
WHEREAS, the Town Council is authorized to provide for the removal of weeds pursuant
to Colorado Revised Statutes §31- 15- 401(1)(d); and
WHEREAS, the Town Council is authorized to implement and enforce the Colorado
Noxious Weed Act, C.R.S. §35 -5.5 -101 et. seq.; and
WHEREAS, C.R.S. §35- 5.5- 108(3) provides that the governing body of a municipality may
declare additional noxious weeds after a public hearing with thirty days notice to the public; and
WHEREAS, notice of the local designation of noxious weeds was posted on August 27, is
2010 in accordance with requirements in Home Rule Charter of the Town of Avon; and
WHEREAS, it is the Town Council's opinion that the health, safety and welfare of the
citizens of the Town of Avon would be enhanced and promoted by the adoption of this
ordinance; and
WHEREAS, approval of this Ordinance on first reading is intended only to confirm that the
Town Council desires to comply the requirements of the Avon Home Rule Charter by setting a
public hearing in order to provide the public an opportunity to present testimony and evidence
regarding the application and that approval of this Ordinance on first reading does not constitute
a representation that the Town Council, or any member of the Town Council, supports, approves,
rejects, or denies this ordinance;
NOW THEREFORE, BE IT ORDAINED BY THE TOWN COUNCIL OF THE
TOWN OF AVON, COLORADO, the following:
Section 1. Recitals Incorporated. The above and foregoing recitals are incorporated herein by
reference and adopted as findings and determinations of the Town Council.
Section 2. Adoption of Local Designation of Noxious Weeds. The Town Council, as the
governing body of the Town of Avon, hereby adopts the local designation of noxious weeds as
•
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 1 of 3
V19.22.10
• such weeds are set forth in the Town of Avon Noxious Weed Management Plan, dated August
27, 2010, attached hereto as Exhibit A.
Section 3. Noxious Weed Management Plan Adopted. The Town of Avon Noxious Weed
Management Plan, dated August 27, 2010, attached hereto as Exhibit A is hereby adopted in its
entirety.
Section 4. Codification Amendments. The codifier of the Town's Municipal Code, Colorado
Code Publishing, is hereby authorized to make such numerical and formatting changes as may be
necessary to incorporate the provisions of this Ordinance within the Avon Municipal Code. The
Town Clerk is authorized to correct, or approve the correction by the codifier, of any
typographical error in the enacted regulations, provided that such correction shall not
substantively change any provision of the regulations adopted in this Ordinance. Such
corrections may include spelling, reference, citation, enumeration, and grammatical errors.
Section 5. Severability. If any provision of this Ordinance, or the application of such provision
to any person or circumstance, is for any reason held to be invalid, such invalidity shall not affect
other provisions or applications of this Ordinance which can be given effect without the invalid
provision or application, and to this end the provisions of this Ordinance are declared to be
severable. The Town Council hereby declares that it would have passed this Ordinance and each
provision thereof, even though any one of the provisions might be declared unconstitutional or
invalid. As used in this Section, the term "provision" means and includes any part, division,
subdivision, section, subsection, sentence, clause or phrase; the term "application" means and
• includes an application of an ordinance or any part thereof, whether considered or construed
alone or together with another ordinance or ordinances, or part thereof, of the Town.
Section 6. Effective Date. This Ordinance shall take effect seven days after public notice
following final passage in accordance with Section 6.4 of the Avon Home Rule Charter.
Section 7. Safety Clause. The Town Council hereby finds, determines and declares that this
Ordinance is promulgated under the general police power of the Town of Avon, that it is
promulgated for the health, safety and welfare of the public, and that this Ordinance is necessary
for the preservation of health and safety and for the protection of public convenience and
welfare. The Town Council further determines that the Ordinance bears a rational relation to the
proper legislative object sought to be obtained.
Section 8. No Existing Violation Affected. Nothing in this Ordinance shall be construed to
release, extinguish, alter, modify, or change in whole or in part any penalty, liability or right or
affect any audit, suit, or proceeding pending in any court, or any rights acquired, or liability
incurred, or any cause or causes of action acquired or existing which may have been incurred or
obtained under any ordinance or provision hereby repealed or amended by this Ordinance. Any
such ordinance or provision thereof so amended, repealed, or superseded by this Ordinance shall
be treated and held as remaining in force for the purpose of sustaining any and all proper actions,
suits, proceedings and prosecutions, for the enforcement of such penalty, liability, or right, and
for the purpose of sustaining any judgment, decree or order which can or may be rendered,
• entered, or made in such actions, suits or proceedings, or prosecutions imposing, inflicting, or
declaring such penalty or liability or enforcing such right, and shall be treated and held as
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 2 of 3
V19.22.10
remaining in force for the purpose of sustaining any and all proceedings, actions, hearings, and
appeals pending before any court or administrative tribunal. •
Section 9. Publication by Posting. The Town Clerk is ordered to publish this Ordinance by
posting notice of adoption of this Ordinance on final reading by title in at least three public
places within the Town and posting at the office of the Town Clerk, which notice shall contain a
statement that a copy of the ordinance in full is available for public inspection in the office of the
Town Clerk during normal business hours.
•
•
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 3 of 3
V19.22.10
• INTRODUCED, APPROVED, PASSED ON FIRST READING, ORDERED POSTED
AND REFERRED TO PUBLIC HEARING and setting such public hearing for October 12,
2010 at the Council Chambers of the Avon Municipal Building, located at One Lake Street,
Avon, Colorado, on September 28, 2010.
Ronald C. Wolfe, Mayor
Published by posting in at least three public places in Town and posting at the office of the Town
Clerk at least seven days prior to final action by the Town Council.
ATTEST:
APPROVED AS TO FORM:
Patty McKenny, Town Clerk Eric Heil, Town Attorney
• INTRODUCED, FINALLY APPROVED, AND PASSED ON SECOND READING, AND
ORDERED PUBLISHED BY POSTING on October 12, 2010.
•
Ronald C. Wolfe, Mayor
Published by posting by title in at least three public places in Town and posting by title at the
office of the Town Clerk.
ATTEST:
Patty McKenny, Town Clerk
Ord. No. 10 -18 Adopting Local Designation of Noxious Weeds
Page 4 of 3
V3 9.22.10
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
TOWN OF AVON
NOXIOUS WEED MANAGEMENT PLAN
ADOPTED BY THE TOWN COUNCIL ACTING AS
THE LOCAL WEED ADVISORY BOARD
ON OCTOBER 12, 2010
The Town of Avon in accordance with "Colorado Noxious Weed Act ", C.R.S. §35 -5.5 -101 et seq.
hereby designates the following plants as Noxious Weeds:
Management Method #
Common Name:
Scientific Name:
1
Leafy Spurge
Euphorbia esula
2
Russian Knapweed
Acroptilon repens
3
Diffuse Knapweed
Centaurea diffusa
4
Spotted Knapweed
Centaurea maculosa
5
Canada Thistle
Cirsium arvense
6
Musk Thistle
Carduus nutans
7
Plumeless Thistle
Carduus acanthoides
8
Scotch Thistle
Onopordum acanthium
9
Houndstongue
Cynoglossum officinale
10
Whitetop/Hoary Cress
Cardaria draba
11
Yellow Toadflax
Linaria vulgaris
12
Oxeye Daisy
Chrysanthemum leucanthemum
13
Dalmatian Toadflax
Linaria dalmatic
14
Common Tansy
Tanacetum vulgare
15
Scentless Chamomile
Matricaria perforate
16
Salt Cedar
Tamarix chinensis
17
Yellow Sweet Clover
Melilotus officinalis
18
Black henbane
Hyoscyamus niger
19
Bull Thistle
Cirsium vulgare
20
Chinese clematis
Clematis orientalis
21
Eurasian watermilfoil
Myriophyllum spicatum
22
Perennial pepperweed
Lepidium latifolium
23
Russian-olive
Elaeagnus angusifolia
24
Spurred anoda
Anoda cristata
25
Sulfur cinquefoil
Potentilla recta
26
Venice mallow
Hibiscus trionum
C7
The purpose of this Noxious Weed Management Plan is to adopt a list of noxious weeds for the
Town of Avon. The basis for this list is set forth in the "Colorado Noxious Weed Act" C.R.S. §35-
5.5 -101 et seq. Weeds which commonly occur in Avon and which are listed on the state's A, B, and
C list at the time of adoption are identified above. In addition, yellow sweet clover ( Melilotus •
officinalis) has been identified as noxious by the Town of Avon. Although this plant is not
Town of Avon: Noxious Weed Management Plan
Page 1 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• currently listed on the state's list, it is identified as noxious by the town and included herein because
it is very invasive, detrimental to cattle, has been found to be problematic in Avon, and is expected
to be added to the state's noxious weed list.2
It is expressly understood in this Plan that the above - referenced list shall be inclusive of all "List A"
species of noxious weeds to the extent they are found within the Town of Avon and identified for
mandatory eradication by the State of Colorado. It is also expressly understood that any and all
"List B" species of noxious weeds not currently listed above, but later found within the Town of
Avon and identified by the state for mandatory eradication pursuant to state regulation 8 CCR 1203-
19, shall be incorporated into this plan and that no amendment hereto shall be necessary prior to
taking enforcement action for the eradication of said species.
The Town of Avon may annually review and update this list of noxious weeds pursuant to state
statute, or sooner if necessary.
Introduction
The noxious weeds that have currently invaded our community have become a threat to the
economic and environmental value of land in the Town of Avon. These weeds are not
indigenous to this county and have no natural predators or diseases to keep them in check.
They are rapidly displacing desirable vegetation causing a loss of productive wildlife
grazing and recreational resources. An integrated noxious weed management plan must
include best practice strategies along with the Federal, State of Colorado, Town of Avon and
Private land owners, working together to meet the challenges we now face in our state.
• II. Goals of this p lan
• Adopting and implementing the Colorado Noxious Weed Act as they apply to the Town
of Avon. The Town of Avon Noxious Weed Regulations as it pertains to noxious weeds
will automatically update along with all future revisions and amendments to the
Colorado Noxious Weed Act.
• Education of the public and private landowners concerning weed management issues
facing our community.
• Work with the Federal, State, County, and private landowners to implement "Best
Management Practices. "
• Identify, inventory and map out noxious weeds currently in our community and use as a
means to monitor our effectiveness and as a tool for future work plans.
III. Weed Management Methods
The Colorado Noxious Weed Act provides that integrated methods must be utilized in the
management of weeds. Integrated methods include but are not limited to: Cultural,
2 This species is listed as invasive in 26 states including Colorado, Arizona, Texas, Wyoming, and Utah. See:
U.S. Forest Service. Weed of the Week: Yellow Sweetclover. Accessed February 2009:
http: / /www.na.fs.fed.us /fhp /invasive plants /weeds /yellow sweetclover.pdf
• Whitson, T.D. (ed.) et al. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative
Extension Services, University of Wyoming. Laramie, Wyoming.
United States Department of Agriculture, Accessed online on April 8, 2010 at
http: / /Dlants.usda.gov/mava /profile ?svmbol =MEOF.
Town of Avon: Noxious Weed Management Plan
Page 2 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
Chemical, Biological and Mechanical management. For proper control of a particular weed •
species, it may be necessary to utilize more than one method. The following general
comments regard control methodology apply to all listed or otherwise identified noxious
weeds, unless otherwise specifically excluded in the detailed management plan listed below
for a particular plant species:
• Cultural — those methodologies or practices conducted to favor the growth of
desirable plants over undesirable plants. Including but not limited to: maintaining an
optimum fertility and plant moisture status in an area, and planting species most
suited to an area. (e.g., Grazing, Revegetation for wildlife)
• Erosion Control — Healthy plant revegetation of all disturbed sites with acceptable
grasses, trees, and other plantings, with a 2 year warranty and extensive weed control
during the re- growth period.
• Chemical — the use of herbicides or plant growth regulators to disrupt the growth of
undesirable plants. (e.g., Herbicides)
• Biological — the use of organisms to disrupt the growth of undesirable plants. (e.g.,
insects, bacteria, pathogens, goats)
• Mechanical — practices that physically disrupt plant growth including but not limited
to: tilling, mowing, burning, cutting, mulching, hand pulling, and hoeing. Tilling,
mowing, mulching, and hoeing are generally only effective if done to plants prior to
the flowering stage. After this stage the seeds have formed and these plants must be
completely removed from- the property by cutting or hand - pulling as part of the •
mitigation effort Cut plants which include buds, flowers, or seed pods should be
placed in clear plastic bags, the bags labeled "noxious weeds ", and landfill disposed.
Landfill disposal should be done through a licensed landscape maintenance
contractor or by direct deposit in the landfill. Unless otherwise recommended below,
no removed weed material which includes buds, flowers, or seed pods should be
burned, composted, or heaped, or otherwise left exposed.
Note that personal protective equipment (PPE) should be worn when conducting weed
mitigation. This may include gloves, long sleeve shorts, full length pants, safety boots, and
safety glasses. Mitigation work should be done carefully because some of the weeds and
herbicides can cause eye and/or skin irritation.
IV. Managed Species Information
Leafy spurge - (Euphorbia esula) a perennial that spreads by seed and creeping rootstocks.
An extensive root system with vast nutrient reserves makes this plant extremely difficult to
control. Management Methods:
a) Cultural: seeding perennial grasses can be an effective management tool. Early emerging
plant species that utilize early season moisture such as smooth brone (Bromus inermis)
or crested wheat grass have reduced leafy spurge density and limited the spread and
establishment of new infestations. Alfalfa can also be a good competitor with leafy
spurge.
b) Chemical: Contact a licensed commercial applicator for specific recommendations for •
herbicide use.
Town of Avon: Noxious Weed Management Plan
Page 3 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• c) Biological: grazing with sheep or goats can stress leafy spurge making it more
susceptible to other control methods. Apthona flava and Apthona nigriscutis are two
species of flea beetles that have been introduced to attack leafy spurge. Adults feed on
foliage during summer and lay eggs at the base of spurge plants. The larvae tunnel the
soil and mine the roots as well as the fine root hairs. These insects along will not control
leafy spurge but they can weaken the plant making it more susceptible to herbicide
treatments or other control methods.
d) Mechanical: mechanical methods have not been proven to be an effective management
tool on this plant.
Comments: A complex of insects, grazing, plant disease and chemical methods will be
necessary to stress the plant sufficiently to attain acceptable control.
2. Russian Knapweed - (Acroptilon repens) A creeping perennial weed which once
established, becomes extremely difficult to control. In heavy infestations few plants can
grow in competition. Management Methods:
a) Cultural: dry range seeded with Crested wheatgrass can cause stress in knapweed by
using up moisture for spring growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: a leaf & stem gall - forming nematode (Subanguina peridus) has been released
in the U.S. This nematode had shown limited success in controlling Russian knapweed
• d) Mechanical: due to the extensive energy reserves in the root system, removal of top
growth alone will not provide adequate control of Russian knapweed. In fact recent
studies have shown that mowing increases Russian knapweed density and stimulates
growth.
3. Diffuse Knapweed - (Centaurea diffusa) is a biennial or short lived perennial which has
become one of the most damaging rangeland weeds in the Northwest inter - mountain area.
Management Methods:
a) Cultural: Seeding of Crested wheatgrass can inhibit the spread of diffuse knapweed in
dry climates
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies (Uphora affins and Uphora quadrifaciata)
attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
4. Spotted Knapweed - (Centaurea maculosa) is a biennial or short lived perennial that
• greatly reduces the range's carrying capacity for both livestock and wildlife. Management
Methods:
Town of Avon: Noxious Weed Management Plan
Page 4 of 14
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
a) Cultural: Good grazing management is one of the best defenses against the spread of •
knapweeds on the range and pasture lands. Proper stocking rates, good livestock
distribution and correct timing and deferment of grazing are essential to the maintenance
of a healthy range or pasture environment.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Two kinds of seed head gall flies ( Uphora affins and Uphora quadrifaciata)
attack the seed heads of Spotted knapweed. The larvae of the files induce galls in
immature flower heads thus directing nutrients away from seed production. These flies
will reduce seed production of the plant but not sufficiently to stop its spread.
d) Mechanical: Deep plowing can reduce the stand density.
Canada Thistle — (Cirsium arvense ) A perennial weed with an extensive root system,
Canada Thistle reproduces both by seed and by vegetation buds on the roots. This requires a
much more extensive management plan than the biennial thistles. Management Methods:
a) Cultural: Cultivation may increase the number of plants by spreading the roots to new
areas where they may become established. Competitive crops, especially alfalfa and
forage grasses may be used to control Canada thistle infestations. Choose aggressive
grass with early season vigor to plant in areas where Canada thistle is present.
b) Chemical: Contact licensed commercial applicator for specific recommendations for •
herbicide use.
c) Biological: Ceutorhynchus litura is a stem weevil whose larvae mine tissues of the leaf,
root crown and root. Outward signs of damage by this larvae are not readily apparent but
secondary damage is caused by other organisms which enter the plants through exit
holes made by the larvae. Urophora cardui is a stem gall fly whose larvae cause galls to
form on the stem of Canada thistle plants. The galls reduce the plant's vigor making it
less able to compete with other plants or to resist pathogens or attacks by other insects. It
is essential that both of these insects be combined with other methods of control for
adequate management of Canada thistle.
d) Mechanical: Mowing can be an effective tool when combined with herbicide treatment.
Mowing alone is not effective unless conducted at two week intervals over several
growing seasons. Mowing should always be combined with cultural and chemical
control.
6. Musk Thistle — (Carduus nutans) is a biennial weed. Biennial weeds are best controlled in
their first year of growth. Very commonly found noxious weed in Eagle County.
Management Methods:
a) Cultural: The best way to prevent or reduce the amount of biennial thistle is to manage
areas that are susceptible to invasion
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use. •
Town of Avon: Noxious Weed Management Plan
Page 5 of 14
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting local Designation of Noxious Weeds
• c) Biological: L Rhinocyllus conicus is a flower head weevil which is widely distributed in
Eagle County. This weevil consumes most of the seeds in the terminal flower heads, but
has no effect on buds which form later in the season. The conicus weevil can be an
effective control method only if it is combined with chemical mechanical controls.
Trichosirocalus horridus is a crown weevil which feeds on the growing tip of the thistle
rosette. This weevil has been released on numerous occasions in Eagle County but has
not yet become established. Due to the very nature of the predator prey cycle the bio
control listed above will not completely eliminate the thistle.
d) Mechanical: Since these thistles are biennials and do not resprout, they are easily killed
by tillage or any method that severs the taproot below the crown of the plant. If dug or
cut after seed heads have formed the plants should be burned or otherwise destroyed so
the seeds will not mature. Mowing is effective only if done when flowers first open.
Comments: A second mowing may be necessary because the plants may recover and
produce viable seed later in the growing season.
7. Plumeless Thistle — (Carduus acanthoides). See description and management method for
the Musk Thistle ( #6 above).
8. Scotch Thistle — (Onopordum acanthium). See description and management method for the
Musk Thistle ( #6 above)
9. Houndstongue — (Cynoglossum officinale) is a biennial weed which is toxic to horses and
cattle. The seed is contained in pods, which are covered with barbs enabling them to stick to
• clothing or animal hair, and thus readily transported. Management Methods:
a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No biological controls are available at this time.
d) Mechanical: Severing the taproot below the crown will control Houndstongue. After
cutting, the plants should be burned or removed if they are in bloom to prevent seed
formation.
10. Hoary Cress Whitetop — (Cardaria draba ) is a perennial plant, which is very competitive
with native vegetation. Its early seeding habits make it difficult to effect control in a timely
manner. Management Methods:
a) Cultural: The effectiveness of mowing or cultivation will be increased if perennial
grasses or alfalfa are seeded as competitor species. Promote healthy grass in rangeland
or pastures by using proper irrigation and fertilization techniques.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
• c) Biological: No insects are known to be effective for controlling this weed.
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
d) Mechanical: No scientific data is available on mechanical control for this species. •
Mowing just prior to seed set may reduce overall seed production, but must repeated
several times during the growing season.
11. Yellow Toadflax - (Linaria vulgaris) This deep- rooted perennial plant is an aggressive
invader of rangeland, pasture and waste areas. Once established on a site it is one of the
most difficult noxious weeds to control. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the amount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a
year for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
12. Dalmation Toadflax — (Linaria dalmatica) An introduced perennial with a creeping root •
system. This plant may suppress desirable grasses even in well managed rangeland or
pastures. Management Methods:
a) Cultural: No data is currently available for the control of Yellow toadflax.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: The Calophasia lunula moth larvae can reduce the root reserves and general
vigor of Yellow toadflax by defoliating new growth and eating buds and flowers.
Gymnetron antirrhini is a capsule weevil which can reduce the amount of seed produced
but has little if any effect on stand density. Combine the use of either of these insects
with chemical or mechanical control for best results.
d) Mechanical: Mowing at bud stage two or three times per year will reduce seed
production but will not effect stand density or duration. Repeated cultivation twice a
year for two years should slow the spread and reduce seed population. This should be
followed by seeding of competitive grasses.
13. Oxeye Daisy — (Chrysanthemum leucanthemum) A member of the sunflower family is an
erect perennial plant with white ray and yellow disk flowers which bloom from June through
August. A native of Eurasia, this aggressive plant has escaped cultivation and become a
troublesome weed in the Intermountain West.
Management Methods:
•
Town of Avon: Noxious Weed Management Plan
Page 7 of 14
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
0 a) Cultural: Maintain range and pasture in good condition through proper irrigation and
fertilization.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known
d) Mechanical: Hand pulling or digging before seed head production can used to effectively
control small infestations. However, for this method to be successful it is important to
remove as much of the underground part as possible.
14. Scentless Chamomile — (Marticaria perforata) An escaped ornamental plant, this annual
has become widely established in the eastern part of Eagle County and is a threat to native
plant communities. Management methods:
a) Cultural: Learn to identify the plant and physically remove them when they first appear.
Seed competitive cool season grasses that out compete this plant at its early stage of
growth.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: No known biological controls
d) Mechanical: Since it is an annual plant, chamomile can be controlled by hand pulling,
cultivation, or any type of physical disturbance.
is15. Common Tansy - (Tanacetum vulgare) An escaped ornamental, is a perennial plant, from
'/2 feet to 6 feet tall with showy button -like flowers. Tansy is a member of the sunflower
family and has become widely established on the western slope of Colorado. Flowering
typically occurs from July to September. Tansy reproduces by both seed and creeping
rootstock. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: None known
d) Mechanical: can be mowed before flowering and seed set to eliminate seed production.
This method may have to be repeated to eliminate regrowth from the rootstock.
16. Salt Cedar (Tamarix chinensis) is a evergreen shrub or small tree which grows near water
and hydric soils and reaches a height of 5 to 20 feet tall. The leaves are small, scale -like and
bluish -green in color. Tiny pink to white colored flowers have five petals and grow on
slender racemes. Salt Cedar reproduces by seed. This is an aggressive plant that
outcompetes native vegetation and consumes a lot of water. Management methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
• to prevent growth of this weed.
Town of Avon: Noxious Weed Management Plan
Page 8 of 14
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
b) Chemical: Contact licensed commercial applicator for specific recommendations for •
herbicide use.
c) Biological: The Salt Cedar Leaf Beetle (Diorhabda elongate) larvae and adults feed on
foliage and can cause plant death if defoliation is consistent. This beetle is commercially
available for distribution.
d) Mechanical: A bulldozer, chainsaw, or prescribed fire can be used in conjuction with
follow -up herbicide treatment for returning sprouts.
17. Yellow Sweet Clover (Melilotus officinalis) is an annual or biennial legume which grows
from 2 to 6 feet tall. It has small yellow to white flowers in a multiflowered terminal and
along auxillary racemes, serrated trifoliate leaves, somewhat resembles alfalfa. It is not
native to Colorado and appears on disturbed sites. It is a drought - tolerant plant. Although
useful for honey producers, it causes bloat in cattle and anticoagulation of blood. The plant
degrades native grasslands and reduces biodiversity by competing for nutrients and by
covering and shading native sun- loving plant species. It reproduces by seed, producing as
many as 100,000 seeds per plant; seeds may remain viable for up to 20 years. Management
Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use. •
c) Biological: Sitona cylindricollis, the sweetclover weevil, may severely damage the plant.
Adults of the insect feed on the foliage and larvae feed on the roots of the plant. A
sweetclover root borer, Walshia miscecolrella, is a native insect that may damage
sweetclover plants on rare occasions. An ash -gray blister beetle, Epicauta fabricii, a
striped blister beetle, Epicauta vittata, and a margined blister beetle, Epicauta pestifera,
have also been found feeding on the plant. Yellow sweetclover is palatable by livestock
- within the risks mentioned above - and plant infestations may be reduced if heavily
grazed.
d) Mechanical: Hand pull early and when the soil is moist. Completely remove all plants
containing seeds. Burning has had variable results, including increasing germination,
and is therefore not recommended.
18. Black henbane (Hyoscyamus niger) was introduced from Europe as an ornamental and
medicinal herb; it is now found across on the western slope of Colorado. A mature plant
reaches 1 to 3 feet in height with foliage that has a fowl odor. Fruits are approximately 1
inch long with 5 lobes. It is often found in disturbed open spaces, roadsides, fields, waste
places and abandoned gardens. It grows in most soil types but likes sandy or well drained
loam soils. The seed viability or longevity is considered to be 1 to 5 years. All parts of
Black henbane are poisonous to both livestock and humans when ingested. The plant is a
strong competitor for moisture and nutrients and produces a persistent litter effecting
germination and growth of native plants. Management Methods:
•
Town of Avon: Noxious Weed Management Plan
Page 9 of 14
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
• a) Cultural: Cultural controls are possible in theory, but are very time consuming and
expensive. Complete removal of any seedlings or newly established plants by continual
hand pulling is also possible.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: N/A
d) Mechanical: Hand pull or dig from moist soil, so the entire tap root system can be
removed. Tillage will control henbane, but is usually not recommended due to the land it
occupies: rangeland, roadsides and pastures. Be sure to bag specimens carefully if
removed during or after flowering.
Comments: A preventable measure is to guard against disturbance and overgrazing.
Controlling plants in the spring or early summer prior to seed production is most effective,
follow -up treatments are recommended to pick up missed or late bolting plants.
19. Bull Thistle (Cirsium vulgare) is a biennial forb that was accidently introduced to North
America as a seed contaminant. In Colorado, Bull thistles are the only species that are
prickly hairy on the top and are cottony -hairy on the undersides of the leaves. Mature plants
can produce up to 4,000 seeds per plant. Commonly seen in areas such as pastures,
overgrazed rangeland, roadsides, and logged areas. It is not especially shade tolerant.
• Bull thistle is an aggressive weed and is often a transient species, appearing in recent clear
cuts or disturbed areas and becoming a dominant species for several years. It has been
reported to cause hay fever in some individuals and is often confused with musk thistle.
Bull thistle infestations have been reported to occur in nearly all Colorado counties west of
the continental divide, in the Upper Arkansas Watershed, and in pockets on the plains.
Heavy infestations can reduce livestock forage. The presence of bull thistle in hay decreases
the forage value and lowers the market price. Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance and
seed dispersal, eliminating seed production and maintaining healthy native communities.
Contact your local Natural Resources Conservation Service for seed mix
recommendations. Maintain healthy pastures and prevent bare spots caused by
overgrazing.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Urophora stylata, a fly predator, is used to help control this thistle. The
female fly lays eggs in the seed head of the thistle. The maggot then consumes the seed
in the flower. This species has overwintered in Colorado but the limited numbers will
not allow for general redistribution. For more information, contact the Palisade Insectary
of the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Because biennial thistles do not reproduce from their roots, any mechanical
or physical method that severs the root below the soil surface will kill the weed. It is
• necessary to revegetate the site with desirable plants. Tillage, hoeing, or even hand-
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
pulling should be successful (not on rangeland), providing it is done before the •
reproductive growth stages.
Comments: The key to effective control is maintaining healthy pastures and rangeland,
guarding against disturbance or overuse, and to limit seed production by collecting and
destroying plants with seeds. Chemical control is most effective when plants are in rosette
stage, spring or early fall. Mechanical controls can be used to eliminate small patches or
plants in a later growth stages.
20. Chinese clematis (Clematis orientalis) is an herbaceous to woody vined perennial which
can climb up to 12 feet. It is native to Eurasia. It has solitary flowers with four yellow
sepals (flowering from August to September) which produces numerous feathery, long -
tailed fruits which are conspicuous all winter. This plant prefers roadsides, riparian
corridors, and rocky slopes although it is sometimes found in open woods. This species can
cause death to young trees and brush. It outcompetes native shrubby and herbaceous species.
Plants will completely cover rock walls, trees, bushes and fences. The juice of freshly
crushed leaves and stems have blister causing agents. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: _ N/A
d) Mechanical: Handpull or dig when soil is moist. Make certain to pull all the roots. Bag
specimens carefully so as to not scatter seeds if flowering. •
21. Eurasian watermilfoil (Myriophyllum spicatum) is an aquatic weed with feathery
underwater foliage that is native to Northern Europe and Asia. Eurasian watermilfoil spreads
most commonly by stem fragmentation, runners, and from free floating plants which
eventually root. It can also spread by seed. The plant is typically submersed with stems to 4
in long. Habitats for Eurasian watermilfoil include: ponds, lakes, rivers, streams, canals, and
ditches. Usually the plant inhabits slow moving water areas but can infest fast moving
water, such as streams and rivers. Eurasian watermilfoil is very invasive. The plant forms
very dense mats of vegetation on the surface of the water. Mats interfere with recreational
activities (e.g. swimming, fishing, skiing, boating, etc.), create mosquito habitat, reduce
native vegetation, and clog intake structures in power generation, irrigation systems, and
potable water intakes. Management Methods:
a) Cultural: Prevention of Eurasian watermilfoil is the best cultural control. Other methods
of cultural controls are possible in theory, but are very time consuming and expensive.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: There is biological control available for Eurasian watermilfoil, but it is not
yet approved for use in Colorado. For more information, contact the Palisade Insectary
of the Colorado Department of Agriculture at 970 - 464 -7916.
d) Mechanical: Hand pulling, raking, harvesting are effective at reducing current
abundance of plants and is useful to clear channels or maintain access. However; it is not •
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
® a very good long term control and is very expensive, labor intensive, and several
removals are needed each year.
Comments: The key to effective control is typically prevention of uncontrolled
monocultures . Chemical and mechanical controls are well developed, but provide short to
medium -term control.
22. Perennial pepperweed (Lepidium latifolium) is an extremely invasive perennial forb
introduced from Europe and Asia as a containment in sugar beet seed. Pepperweed
reproduces both by seed and vegetatively by roots and shoots. Pepperweed has tiny white
spoon- shaped petals on the flowers. It readily invades disturbed and bareground areas.
Pepperweed is a serious threat because it alters ecosystems by acting as a "salt pump"
absorbing salts from deep in the soil. The plant then excretes the salt through the leaves and
deposits it on the surface soil. Since most desirable plants do not tolerate high saline
concentrated soils, the entire plant composition and diversity of the area changes. Large
monocultures and dense litter layers prevent native plants from regenerating. Pepperweed
displaces native plants and wildlife habitats, reduces food quality for wildlife and reduces
agricultural and pasture production. Management Methods:
a) Cultural: Prolonged spring flooding of new growth will kill pepperweed. Grazing is not
recommended because the plant may be toxic. Reestablishing the native or desired plants
can take years, so repeat plantings must be repeated, but it can aid in controlling
populations.
• b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Biological control is not a viable option because 11 other species of native
Lepidium are on the Endangered species list, and the risk to these species as well as
agricultural species is too great.
d) Mechanical: Due to the deep, brittle root, most mechanical methods are not recommend,
and can actually propagate, spread and increase the density of pepperweed. Hand pulling
can also bring seeds to the soil surface, and spread pieces of root, which will sprout.
However, spring mowing combined with chemical treatments can be effective.
Comments: It is important to prevent establishment of large populations via early detection
and removal. Planting desirable and competing grasses and forbs is recommended
Herbicide treatments are a good option if used during the bud to flowering stage of the plant.
23. Russian -olive (Elaeagnus angusifolia) is a perennial tree or shrub that is native in Europe
and Asia. The plant has olive - shaped fruits, silver color at first then becoming yellow -red
when mature. Russian olive can reproduce by seed or root suckers. Seeds can remain viable
for up to 3 years. The plants extensive root system, sprouts root suckers frequently. The
lower surface is silvery white with dense scales, while the upper surface of the leaf is light
green in color. Previously thought to be a beneficial windbreak tree, it since has been
deemed detrimental to the environment because it competes native vegetation, interferes
with natural plant succession and nutrient cycling, and taxes water reserves. Russian olive
can grow in a variety of conditions. Although Russian-olive provides a plentiful source of
is edible fruits for birds, ecologists have found that bird species richness is actually higher in
riparian areas dominated by native vegetation. The key to effective control of Russian olive
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
is preventing establishment of the trees or shrubs. The state of Colorado mandates control •
state -wide and requires eradication in most riparian areas. Management Methods:
a) Cultural: N/A
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
Biological: Tubercularia canker overwinters on infected stems and spreads via rain -
splash, animals, or pruning implements to open wounds in the bark. Infected tissue
becomes discolored or sunken. Entire stems may be girdled and killed, and the disease
can deform or kill stressed plants over time. For more information, contact the Colorado
Department of Agriculture's Insectary in Palisade, Colorado at 970 - 464 -7916.
d) Mechanical: Cut down the tree. Mowing with a brush type mower, followed by removal
of cut material, is another options for smaller shoot - hedges. Stump sprouting commonly
occurs after cutting down the tree, and excavation of the entire stump can trigger root
sprouting. Burning is practical when conditions support a long hot fire and most
effective in summer or early fall (burn permit required, call the Eagle River Fire
Protection District at 748 - 9665).
Comments: As a water conservation measure, Avon requires elimination of existing Russian
Olive trees from water courses but allows continued stand on higher ground where property
owners commit to control measures. Avon's weed management requirements on this
species are as follows:
• Removal is required if the tree is within 25 feet of the high water mark of a permanent •
creek, stream, river; or within 25 feet of the top or rim of an irrigation canal, ditch or
ephemeral water course.
• Removal or control is allowed if tree is outside of water course boundaries.
A written commitment by the property owner or property manager for controlling the spread
of this species must be on -file to remain in compliance with Avon's Noxious Weed
Ordinance. Contact Avon Public Works, 500 Swift Gulch Rd, Avon 81620, call 970 -748-
4100 or by e -mail at weeds gavon.org.
Replacing with native trees is important once Russian olive has been removed, and is
required when the tree had previously been part of approved site landscaping. Contact Avon
Community Development at 970 - 748 -4030 for information about modifying your
landscaping plan.
24. Spurred anoda ( Anoda cristata) is a summer annual forb with a low growing, spreading
profile. The seedlings have one round and one heart- shaped cotyledon with hairs along the
margins of the leaves. The flowers appear August through November and are light blue to
lavender in color. Habitats include: ditches, within crops, along roadsides, gardens, waste
areas and disturbed sites. Spurred anoda is considered an agricultural weed and is found
mainly in agricultural crops (corn, cotton, beans, etc.). Management Methods:
a) Cultural: Prevent the establishment of new infestations by minimizing disturbance.
Revegetation and active management of revegetated areas is needed for disturbed areas
to prevent growth of this weed. •
Town of Avon: Noxious Weed Management Plan
Page 13 of 14
8/27/2010
EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
b) Chemical: N/A
c) Biological: N/A
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully as not to spread seeds.
Comments: Preventing seed production is key. Small patches can be controlled by hand
pulling or hoeing
25. Sulfur cinquefoil (Potentilla recta) is a perennial forb that is native to Eurasia. Leafstalks
have conspicuous perpendicular hairs and leaves appear green on the underside; plants can
grow 28 inches in height. The flowers are pale yellow. Sulfur cinquefoil grows on dry
sandy, gravelly, and rocky soils. Bareground is prime habitat for weed invasions. It is important
to properly identify sulfur cinquefoil, since it resembles the native cinquefoils. Management
Methods:
a) Cultural: Increasing the competitiveness of native species can assist in preventing
establishment of Sulfur cinquefoil. Contact your local Natural Resources Conservation
Service for seed mix recommendations.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
herbicide use.
c) Biological: Biocontrol species have been used in trials, since Sulfur cinquefoil is similar
• to strawberries though, the insects used are considered pests. For more information,
contact the Colorado Department of Agriculture's Insectary in Palisade, Colorado at
970 - 464 -7916.
d) Mechanical: Mowing is not effective, as new shoots will replace the cut steams. Hand
dig or pull when soil is moist is effective on small infestations. Be sure to dig up as
much of the root system as possible, especially since root fragments can produce new
plants.
Comments: Hand pulling or digging when infestations are small and the soil is moist
combined with use of herbicides has proven to be effective.
26. Venice mallow (Hibiscus trionum) is a summer annual forb that has a spreading profile and
is native to Europe. The seeds are dark brown and can remain viable for 50 years. The
cotyledons are round with hairy petioles. The stems are erect and hairy, growing to about 18
inches tall. The first true leaves have toothed margins and are alternate. Flowers are a light
sulfur to yellow color with a red to purple center which only last a couple of hours. Venice
mallow is an agricultural weed. Management Methods:
a) Cultural: Outcompeting Venice mallow, is difficult with native grasses and forbs, since
Venice mallow likes agricultural crop areas. But, contact your local Natural Resources
Conservation Service for seed mix recommendations that may help in rangeland areas.
Bareground is prime habitat for weed invasions.
b) Chemical: Contact licensed commercial applicator for specific recommendations for
• herbicide use.
c) Biological: N/A
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
d) Mechanical: Hand pulling or digging when soil is moist, making sure to get the roots to •
prevent resprouting. Removing flowers before the plant sets seed will also be effective.
Be sure to bag specimens carefully so as not to spread seeds.
Comments: Best control is to prevent establishment of the plant and seed production with
early detection and physical removal. Herbicide treatments are another control option.
Multiple applications or a pre- emergence application will be most effective. When soils are
moist, hand pulling or digging is effective provided that you bag the removed plants.
V. Acknowledgements
The Town of Avon sincerely appreciates the great work done by botanists, scientists, and
others at the State of Colorado, Department of Agriculture and at the Colorado State
University Extension offices. These resources were the primary source of all of the
technical information contained in this plan. State and CSU staff reviewed this document
prior to the Town's 2010 adoption.
•
•
Town of Avon: Noxious Weed Management Plan
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EXHIBIT A: TOWN OF AVON NOXIOUS WEED MANAGEMENT PLAN, dated August 27, 2010
Exhibit A to Ordinance No. 10 -18 Adopting Local Designation of Noxious Weeds
® State of Colorado
is
•
Department of Agriculture
Noxious Weed Program
(303) 239 -4100
http://www.colorado.gov/cs/Satellite/Agriculture-Main/CDAG/I 17408404873 3
Colorado State University Extension
Eagle County Office
P.O. Box 239
441 Broadway
Eagle CO 81631
(970) 325 -8630
http://www.eaglecounty.us/csu/
For more information, including color photos of all the species listed here, please
contact either of the above resources.
If you have general questions on noxious weeds or have received a noxious weed
violation notice, please call Avon Public Works at (970) 748 -4100.
Town of Avon: Noxious Weed Management Plan
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