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HomeMy WebLinkAboutR00-045 Weed Management Plan Amended L \ Commissioner Ph moved adoption of the following Resolution: BOARD OF COUNTY' COMMISSIONERS COUNTY OF EAGLE, STATE OF COLORADO RESOLUTION NO. 2000 -IC ADOPTING AN AMENDED WEED MANAGEMENT PLAN FOR THE UNINCORPORATED AREAS OF EAGLE COUNTY WHEREAS, C.R.S. 35 -5.5 -105 et seq. (known as the "Colorado Weed Management Act "), mandates the board of county commissioners of each county in the state to adopt an undesirable plant manage- ment plan for all of the unincorporated lands within the county, and sets forth powers and duties to enable each board to comply with said Act; and WHEREAS, on April 27, 1998, after notice, the Board desig- nated a list of fifteen noxious weeds pursuant to C.R.S. 35 -5.5- 107 attached hereto as Exhibit A; and WHEREAS, the Board of County Commissioners of Eagle County, Colorado ( "the Board "), in order to implement the provisions of the Act, did appoint the Eagle County Weed Management Advisory Commission, which developed a. recommended plan for the integrated management of designated undesirable plants and management criteria ( "the Plan ") for consideration by the Board; and WHEREAS, the most recently adopted Weed Management Plan was adopted in 1994 through Resolution 94 -148; and WHEREAS, having reviewed the proposed amended Plan, the Board finds it to be in the best interest of the continued economic and environmental value of the lands within Eagle County to adopt the Plan as recommended. NOW, THEREFORE, BE IT RESOLVED BY THE BOARD OF COUNTY COMMISSIONERS OF THE COUNTY OF EAGLE, STATE OF COLORADO: THAT, the list designating noxious weeds adopted after public hearing on April 27, 1998, attached as Exhibit A, is the official noxious weed list for Eagle County pursuant to C.R.S. 35 -5.5 -107. THAT, the Eagle County Weed Management Plan, as set forth in Exhibit "B" attached hereto and incorporated herein by this reference, be and is hereby adopted. THAT, in accordance with C.R.S. 35 -5.5 -107, the Weed Manage- ment Advisory Commission shall review the Plan no less often than once every three years, and shall make recommendations to the Board concerning the continued appropriateness of the Plan. THAT, the Board hereby finds, determines and declares that this Resolution is necessary for the health, safety and welfare of the citizens of Eagle County. MOVED, READ AND ADOPTED by the Board of County Commissioners of the County of Eagle, State of Colorado, at its regular meeting held the day ofctaili,, 2000. COUNTY OF EAGLE, STATE OF , COLORADO, By and Through Its ATTEST BOARD OF COUNTY COMMISSIONERS • i — erk to the 'Board of "' Tom C. Stone County Commissioners Chairman 14 iii elk, 1 hael L. allagh./r Commissioner / / " /i ohnnette Phils • • Commissioner Commissioner OdY seconded adoption of the foregoing resolution. The roll having been called, the vote was as follows: Commissioner Stone 0 _,i Commissioner Gallagher Commissioner Phillips 1 This Resolution passed by 3 'C7 vote of the Board of County Commissioners of the County of Eagle, State of Colorado. G:\MTA\R\WEEDPLAN.2K.wpd File 86 -108 1 e EXHIBI .'.w o Alre itV 4, • • EAGLE COUNTY, COLORADO "LEGAL NOTICE" FOR IMMEDIATE RELEASE Date: April 17, 1998 Contact: Tom Girard, Eagle County Weed & Pest (970)328 -8778, Fax: (970)328 -6444 Eagle County Noxious Weed Designation Eagle, CO - The Eagle County Weed Advisory Committee has proposed that the following plants be designated as noxious weeds under the provisions of The Colorado Weed Management Act, Title 35 Article 5.5 -107: 1. Leafy spurge (Euphorbia esula) 2. Russian knapweed (Centaurea repens) 3. Diffuse knapweed (Centaurea diffusa) 4. Spotted knapweed (Centaurea maculosa) 5. Musk thistle (Carduus nutans) 6. Canada thistle (Cirsium arvense) 7. Plumeless thistle (Carduus acanthiodes) 8. Scotch thistle (Onopordum acanthium) 9. Houndstongue (Cynoglossum officianale) 10. Whitetop (Cardaria draba) 11. Yellow toadflax (Linaria vulgaris) 12. Dalmation toadflax (Linaria dalmatica) 13. Common burdock (Arctium minus) 14. Wild carroway (Carum carvil) 15. Scentless chamomile (Anthemis arvensis) A public hearing will be held on April 27, 1998 at 10:45 am in the Eagle County Room of the Eagle County Building. After the hearing, this list of plants will be submitted to the Board of County Commissioners for final approval and adoption by resolution. Any questions or concerns regarding this issue should be directed to Eagle County Weed & Pest, P.O. Box 239, Eagle CO 81631. (970)328 -8778. Fax: (970)328 -6444. tAMttit 1 fJ EAGLE COUNTY WEED MANAGEMENT PLAN (as of 01/13/00) Introduction Several species of non - native plants have become a threat to the economic and environmental value of land in Eagle County. These plants are not indigenous to this country and have no natural predators or diseases to keep them in check. They are rapidly displacing desirable vegetation causing a loss of productive grazing and recreational resources. The state of Colorado has mandated that a county -wide plan must be implemented to prevent further damage by these noxious weed species. II. Goals of this plan A. Implementation of "Title 35 Article 5.5, The Colorado Weed Management Act "as it applies to unincorporated lands in Eagle County. B. Education of the public concerning weed management issues. Generate public support for the program. C. Work with in Eagle County government departments to institute "Best Management Practices" that stress the importance of prevention and address areas that could be streamlined. D. Foster a spirit of cooperation among federal, state and local governmental agencies and private landowners by working with these agencies to institute "Best Management Practices ". E. Develop county -wide noxious weed inventory to ensure sound management strategies are implemented. III. Statement of weed problem A. Thousands of acres of land in Eagle County are already infested with weed species listed in this document. Experts in weed science estimate this figure increases 15 percent annually with if no control measures are imposed. Such an increase in weed populations pose a serious threat to the economic and environmental value of land in Eagle County. B. The weed problem in Eagle County is of concern not only to the agricultural community, but to the urban, recreational and small landowner communities as well. Problem areas include: road sides, railroad lines, housing subdivisions, municipal areas, private property, state and federal lands. 1 C. The following weeds have been designated by the Eagle County Board of Commissioners to be undesirable and must be controlled (per public hearing April 27 1998): 1. Leafy spurge (Euphorbia esula) 2. Russian knapweed (Centaurea repens) 3. Diffuse knapweed (Centaurea diffusa) 4. Spotted knapweed (Centaurea maculosa) S. Musk thistle (Carduus nutans) 6. Canada thistle (Cirsium arvense) 7. Plumeless thistle ( Carduus acanthiodes) 8. Scotch thistle (Onopordum acanthium) 9. Houndstongue (Cynoglossum officianale) 10. Whitetop (Cardaria draba) 11. Yellow toadflax (Linaria vulgaris) 12. Dalmation toadflax (Linaria dalmatica) 13. Common burdock (Arctium minus) 14. Wild carroway (Carum carvil) 15. Scentless chamomile (Anthemis arvensis) D. The control of undesirable plants shall be the responsibility of the landowner. Technical advice and support will be provided by Eagle County Weed & Pest and the Colorado State University Cooperative Extension office. IV. Priorities A. Education: Education is pivotal to the sustainable success of this weed management plan. Most weed species, if detected early, can be managed. Groups targeted for public education include those with agricultural interests, homeowners associations, green industry, developers, recreational groups, youth groups and schools. This instruction will be provided by the Eagle County Weed & Pest Department and other government agencies. Workshops will be held throughout the year to provide information on the following subjects: 1. Noxious weed identification & management methods. 2. Mapping techniques 3. Compliance with the "Colorado Weed Management Act" C.R.S. 35 -5.5. 4. Private applicator training. 2 5. Integrated pest management. B. Improve weed management practices on County owned land and rights -of -way to include all weed species listed in this plan. This work will be completed by the Eagle County Weed & Pest Department, or their assignees. C. Mapping: In a continuing effort to manage noxious weeds with sound stragety, existing noxious weed inventories will be compared to new mapping data. This data will encompass properties of County, BLM. USFS, major rights -of -way not county maintained and private lands at land holders request or permission. D. Cooperative agreements: Cooperative agreements will be sought between Eagle County and federal, state and local governments to facilitate a coordinated effort in managing the weed species listed in this document. E. Prevent establishment of new invasive species and manage existing populations to prevent spread to previously un- infested areas. F. Establish guidelines for revegetation through a cooperative effort with other county government entities. V. Plan of Work A. Goals (short term) 1. Increase public awareness of "Colorado Weed Management Act." ( C.R.S. 35 -5.5) 2. Control undesirable plants on county properties and rights -of -way. Prevent further spread of Leafy spurge from existing sites 3. Revisit and renew cooperative agreements with federal, state and local governments to maximize weed control efforts within Eagle County. 4. Reach County residents through educational workshops, private consultations and newspaper articles. 5. Update existing mapping and encourage new mapping of federal, state, incorporated and private lands within Eagle County. 6. Develop a cooperative spirit within county agencies to encourage prevention of noxious weeds through pro- active planning efforts. 3 B. Goals (long term) 1. Manage existing weed infestations aggressively to prevent spread and reduce weed density. 2. Develop and implement revegetation requirements in cooperation with other Eagle County entities. 3. Aggressively fight all new invasive species through education and quick response. 4. Complete weed inventories in Eagle County and develop a GIS weed layer encompassing federal, state, county, municipal and private land holdings. 5. Investigate the expansion of biological release sites to include all areas of County. VI. Management Methods: See Appendix A A. Non - Compliance ( per Eagle County RESOLUTION NO. 94 -148) : 1. Private Lands: a. If, following inspection pursuant to C.R.S. §35 -5.5- 109(1), land is found to contain designated undesirable plants, the landowner shall be given written notice, personally or by certified mail. The notice shall name the undesirable plants, identify the location of the plants, advise the landowner to control the undesirable plants, and specify the best available control methods of integrated management. The notice shall offer to consult with the landowner in the development of a management plan for the control of undesirable plants on the land. The notice also shall state that the landowner shall, within a reasonable time not to exceed ten days, either (I) comply with the terms ofthe notification, (II) acknowledge the terms of the notification and submit an acceptable plan and schedule for the completion of the plan for compliance; or (III) request an arbitration panel to determine the final management plan. b. If the landowner chooses action option I, the Weed and Pest Department will reinspect the land to confirm compliance. c. If the landowner chooses action option II, the Weed and Pest Department will review the proposed weed management plan and determine its efficacy. If the plan is acceptable, no further action will be taken except 4 to monitor compliance, including reinspection. d. If the landowner chooses action option III, an arbitration panel will be selected by the Board of County Commissioners and a hearing shall be set for a time and date as soon as practicable after the panel is complete. The Weed and Pest Department shall give written notice, personally or by mail, of the hearing to any complainant. The landowner is entitled to appear before the panel, individually and /or by representative, as is any complainant. The arbitration panel will be required to determine the final management plan within not more than two calendar weeks after the hearing is completed. e. If the landowner fails to comply with the notice to control the designated undesirable plants, fails to submit an acceptable management plan, fails to comply with an accepted management plan or fails to comply with a management plan as determined by the arbitration panel, the property shall be deemed to be a public nuisance for which the remedies for abatement of a public nuisance shall be available as provided in C.R.S §35 -5.5 -113, and the Weed & Pest Department shall give written notice thereof to the landowner by personal delivery or by certified mail which notice will include (I) description of the land, (ii) name of the undesirable plants and their location (s) on the land, (iii) date the Weed & Pest Department will perform weed control on the land, (iv) method of control to be applied, (v) a statement that the land will be assessed the entire cost of the weed control plus 15% surcharge for the cost of inspection and other incidental costs, which total will be a lien on the land (or the tract of which it is a part) until paid, and (vi) a statement that should the landowner refuse admission to the land for application of the weed control, the County will seek civil and /or criminal penalties and court- enforced abatement of a public nuisance. f Whenever the land is known to the Weed & Pest Department to be occupied by someone other than the record owner, written notices also shall be given to the occupant, and the occupant shall be informed that C.R.S. §35- 5.5 -109 imposes on occupants the same responsibilities for undesirable plant control as it imposes on landowners. g. Whenever notice is given by mail, it shall be deemed given when deposited in a regular depositary of the United States Postal Service, postage prepaid. Notice to landowners shall be mailed to the last known address as shown in the County's Assessment Roll unless the landowner has provided the Weed & Pest Department a different address for notice. Notice to occupants shall be mailed to the land's physical address unless the occupant has provided the Weed & Pest Department a different address for notice. 2. Public lands: Per C.R.S. §35 -5.5 -110 5 3. Federal and state lands: Per C.R.S. §35 -5.5 -111 4. Public Rights -of Way: Per C.R.S. §35.5 -112 B. Establish Weed Management Areas. 1. Identify areas requiring intensive management (severe weed problems). 2. Manage weeds across property lines and . jurisdictional boundaries by establishing cooperative weed management projects with multiple landowners and government agencies. 3 Identify methods of noxious weed control in environmentally sensitive areas i.e. Wetlands, Waterways, wilderness areas. 4 Identify methods of control for subdivisions and residential areas. C. Solicit public input through public meetings. VII. Conclusion: Many non - native species of weeds that have become established here are deep rooted perennial plants that are extremely difficult to control. Eradication of these species is not a realistic goal. We can, however, through a concerted cooperative effort, manage these plants to prevent further disruption of the many and varied plant communities that make up our inter - mountain region. Respectfully submitted by: Chairman, Eagle County Weed Advisory Commission _Auld Oita Secretary, Eag e County Weed Advisory Commission / — O 0 Date Prepared by Paul Schreiner Eagle County Weed & Pest Coordinator 6 APPENDIX A Weed management methods A. Definitions: The Colorado Weed Management Act ( C.R.S. 35 -5.5 )states 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. 1. It is to be understood that many or all of these methods may be inadequate for control as a stand alone solution. Particularly cultural, mechanical and biological methods will need support from one or more methods mentioned. A method will not be considered adequate if the percentage stand reduction in question is less than 15 percent per growing season. The following definitions for these integrated methods will be used in this weed management plan: a. 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. b. Chemical - the use of herbicides or plant growth regulators to disrupt the growth of undesirable plants. c. Biological - the use of organisms to disrupt the growth of undesirable plants. d. Mechanical - practices that physically disrupt plant growth including but not limited to tilling, mowing, burning, mulching, hand pulling and hoeing. B. The following guidelines have been developed to assist landowners in selecting effective weed control methods. Individual weed management plans will be evaluated using these guidelines. Individual weed management plans utilizing control methods not included in these guidelines will be judged on their own merit. 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 and forbs can be an effective management tool. Early emerging plant species that utilize early 7 season moisture such as Smooth brome (bromus inermis) or Crested Wheatgrass 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 Eagle County Weed and Pest or 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 through the soil and mine the roots as well as the fine root hairs. These insects alone 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 diseases and chemical methods will be necessary to stress the plant sufficiently to attain acceptable control. 2. Russian knapweed (Centaurea repens) - A creeping perennial weed which once established, becomes extremely difficult to control. In heavy infestations few plants can grow in competition. Allelopathic chemicals have been extracted from Russian knapweed. Management methods: a. Cultural - dry range seeded with Crested wheatgrass can cause stress in knapweed by using up moisture for spring growth. b. 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. From "Non- chemical Alternative for Managing Selected Plant Species ". Dr. Wayne Leminger, Colorado State University. 2 Care should be taken when moving animals from infested areas to un- infested areas to prevent seed transport and spread. 3 Allelopathic- containing chemicals which are toxic to other plants, thus reducing competition from them. 8 c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. 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 mowing to increase russian knapweed density and stimulates growth'. 3. Spotted knapweed (Centaurea maculosa) - Spotted knapweed 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 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. Biological - Two kinds of seed head gall flies (Uphora affinis and Uphora quadrifaciata) attack the seed heads of Spotted knapweed. The larvae of the flies 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. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. d. Mechanical - Deep plowing can reduce the stand density. 4. Diffuse knapweed - Diffuse knapweed 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 4 Studies conducted br Dr. George Beck, Colorado State University Weed Scientist. 1993, Study conducted by A. Wayne Cooley, Colorado State University Extension Agent, Tri River Area, 1998. 5 Non - Chemical Alternative for Managing Selected Plant Species, Dr. Wayne C. Leininger, Colorado State University 9 b. Biological - Same as Spotted knapweed c. Chemical - Same as Spotted knapweed d. Mechanical - Same as Spotted knapweed 1. Comments: Early detection and management of invading plants is the key to managing knapweeds. 5. Musk thistle, Plumeless thistle and Scotch thistle are all biennial weeds which require the same management methods.- Biennial weeds are best controlled in their first year of growth (rosette stage). This group of thistles are the most commonly found noxious weed in Eagle County. a. Cultural- The best way to prevent or reduce the amount of biennial thistle is to manage areas that are susceptible to invasion in such a way as to promote vigorous stands of competing vegetation. Grasses such as Tall fescue have been proven to be effective competitors against the biennial thistles. Overgrazing should be avoided as biennial thistle rosettes have been shown to increase under these conditions. b. 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 or 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. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. 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 seedheads 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. A second mowing may be necessary because the plants may recover and produce viable seed later in the growing season. 10 6. Canada thistle - A perennial weed with an extensive root system, Canada thistle reproduces both by seed and by vegetative buds on the roots. This weed requires a much more extensive management plan than the biennial thistles. Successful management of Canada thistle will only be accomplished by combining two or more of the control methods listed below. 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 grasses with early season vigor to plant in areas where Canada thistle is present. b. 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 is 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. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. 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. 7. Houndstongue - Houndstongue 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 be readily transported. a. Cultural - Maintain range and pasture in good condition through proper irrigation and fertilization. b. Biological- No biological controls are available at this time. c. Chemical- Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. d. Mechanical - Severing the taproot below the crown will control houndstongue. After cutting, the plants should be burned or removed 11 if they are in bloom to prevent seed formation. 8. Whitetop - Whitetop or Hoary cress 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. 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. Biological - No insects are known to be effective for controlling this weed. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. 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 be repeated several times during the growing season. 9. Yellow toadflax - 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. a. Cultural - No data is currently available for the control of Yellow toadflax. b. 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. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. 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 10. Dalmation toadflax - An introduced perennial with a creeping root system. This plant may suppress desirable grasses even in well managed rangeland or pastures. Management methods used for Yellow toadflax may also be used on Dalmation toadflax. 11. Common burdock - A biennial weed that can grow to a height of ten feet. Burdock produces many large burs which can become embedded in animals hair or attached to clothing allowing the seed to be widely distributed. a. Cultural - Prevent the establishment of Burdock by keeping pasture and rangeland in good condition through the use of proper irrigation and fertilization methods. b. Biological - No data exists that demonstrates viable options for insect control or livestock grazing as management methods. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. d. Mechanical - Severing the root of the young rosette below the crown with a shovel or other sharp implement will kill the plant. Cultivation two times per year will reduce seed production and slow the spread of burdock. Cultivation should be performed during the bud stage of growth and repeated if the plants bud again. 12. Wild carroway - Originally introduced into this country as a cultivated plant, this aggressive biennial can decrease meadow hay production by as much as 30% once it becomes established. a. Cultural - Clean all haying equipment when moving from infested to uninfested hayfields to prevent the spread of this weed. Encourage healthy stands of grass in hayfields through the proper use of irrigation and fertilization techniques. b. Biological - There is no research available on biological control of carroway. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. d. Mechanical - No specific recommendations' are known, however, mowing or cultivation when possible could reduce seed production and stand density. 13 13. Scentless chamomile - 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. 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. Biological - No known biological controls. c. Chemical - Contact Eagle County Weed and Pest or a licensed commercial applicator for specific recommendations for herbicide use. d. Mechanical - Since it is an annual plant, chamomile can be controlled by hand pulling, cultivation, or any type of physical disturbance. 14