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20240815 6584 McLin and Murray Yards Noxious Weed Management Plan
Noxious Weed Management Plan 6584 MITCHELL CREEK TO UTE RIFLE TRANSMISSION LINE STAGING AREAS – MCLIN and MURRAY YARDS Garfield County, Colorado August 8, 2024 _______________________________________________________ Prepared for: Xcel Energy PO BOX 840 Denver, Colorado 80201 (720) 963 -3684 _______________________________________________________ Prepared by: HDR, Inc 1670 Broadway, Suite 3400 Denver, CO 80202 _______________________________________________________ Noxious Weed Management Plan | 6584 Transmission Line Staging Areas TOC-i Contents Page No. Section 1. Introduction ............................................................................................................. 1 1.1 Project Description ......................................................................................................... 1 Section 2. Noxious Weed Management Requirements .............................................................. 1 2.1 Presidential Executive Order 13112 —Invasive Species ................................................... 1 2.2 Colorado Noxious Weed Act ........................................................................................... 2 2.3 Garfield County Noxious Weed Management .................................................................. 2 Section 3. Noxious Weed Survey Methods ............................................................................... 3 Section 4. Study Area Description ............................................................................................ 4 4.1 Location ......................................................................................................................... 4 4.2 Topography and Hydrology ............................................................................................. 4 4.3 Land Use ....................................................................................................................... 4 4.4 Climate .......................................................................................................................... 4 4.5 Vegetation and Habitat ................................................................................................... 4 Section 5. Noxious Weed Survey Results ................................................................................. 5 Section 6. Noxious Weed Management .................................................................................... 6 6.1 Noxious Weed Treatment Measures ............................................................................... 7 Section 7. Recommended Management and Mitigation Actions ................................................. 9 Section 8. References............................................................................................................ 10 Appendices Appendix A. Figures Appendix B. Representative Photographs Appendix C. Plant List Appendix D. Noxious Weed Fact Sheets Tables Table 1. Colorado State Noxious Weed Species Observed in the Project Study Area ......... 5 Table 2. Noxious Weed Species Recommended Control Techniques ................................ 8 August 2024 Page 1 Section 1. Introduct ion The Public Service Company of Colorado (PSCo), a Colorado corporation conducting business as Xcel Energy (Xcel), is proposing to rebuild a 25 -mile segment of a 69 -kilovolt (kV) overhead transmission line from the Mitchell Creek Substation to the Ute Rifle Substation on the 6584 Transmission Line (Project). This rebuild is within the City of Glenwood Springs , Town New Castle, City of Rifle, and unincorporated Garfield County, Colorado . Staging areas for the project include the McLin and Murray Yards, which are in unincorporated Garfield County, Colorado. On behalf of Xcel, HDR Engineering, Inc. (HDR) conducted a noxious weed survey for the staging yards. This Noxious Weed Management Plan (Plan) has been prepared to support the installation of prescribed seed mixes, management of noxious weeds, and to comply with federal, state and local requirements regarding noxious weeds in the Project area. 1.1 Project Description The project will utilize multiple staging areas for the overnight storage of equipment and material associated with the transmission line build. All other yards and the transmission line will be permitted separately. The Murray and McLin Yard s are in unincorporated Garfield County and will be associated with the phase 1 build (Appendix A – Project Overview Figure). The McLin and Murray Yards are respectively located southeast and southwest of the town of Silt, Colorado. The 36-acre Murray Yard is located approximately 1 mile west-southwest of the intersection of County Road 3 31 and 346. Access to the yard will be from Chair Bar Road which boarders the north and east perimeter of the staging yard. The McLin Yard is located approximately 0.75 miles southeast of the intersection of County Road 311 and 335. Access to the 15-acre yard McLin Yard will be from County Road 311 . Construction is anticipated to begin in September of 2024 and end January of 202 5. The McLin Yard is located within Section 16 of Township 6 South, Range 92 West and the Murray Yard is located within Section 13 of the same Township and Range of the Public Land Survey System. Section 2. Noxious Weed Management Requirements When present in large numbers, noxious plant species have had considerable impacts to the quality and integrity of natural ecosystems. Noxious weed species can alter fire ecology, successional ecosystem processes, and ecosystem function of the ecosystems they invade. Some species have had such serious economic and biological impacts that their control and management is mandated under Colorado State law (i.e., List A species). Because of the adverse environmental effects of noxious weeds, federal and state governments have issued various orders and regulations regarding noxious weeds. The following are some of the regulations guiding noxious weed management. 2.1 Presidential Executive Order 13112 —Invasive Species Executive Order 13112 , Invasive Species, was issued on February 3, 1999, to prevent the August 2024 Page 2 introduction of invasive species; provide for their control; and minimize the economic, ecological, and human health impacts that result from invasive species. This order directs federal agencies to prevent the introduction of invasive species, control and monitor invasive species, and restore native species and habitats that have been invaded (Federal Register 1999). 2.2 Colorado Noxious Weed Act As defined by the Colorado Department of Agriculture (CDOA), noxious weeds are plants that reduce agricultural productivity, lower real estate values, endanger human health and well -being, and damage scenic values (CDOA 20 24a). The Colorado Noxious Weed Act §§ 35 -5.5-101 through 119, C.R.S. as amended, states that an organized and coordinated effort must be made to stop the spread of noxious weeds. Rules pertaining to administration of the Act include a noxious weed list that designates and classifies noxious weed species into categories for immediate eradication (CDOA 20 24a): • List A contains 24 species of noxious weeds targeted for eradication. If individuals or populations of A List species are found, the local governing body must provide the State Weed Coordinator with mapping that includes information on location and density of the infestatio n. • List B contains 3 5 species that are targeted for eradication, containment, or suppression based upon a given local governing body’s management plan. • List C contains 1 8 species for which the Commissioner of Agriculture, in consultation with the state noxious weed advisory committee, local governments, and other interested parties, will develop and implement into state noxious weed management plans designed to support the efforts of local governing bodies to facilitate more effective integrated weed management on private and public lands. In addition to the three lists, the state maintains a noxious weed species “Watch List”. It contains 19 species that CDOA has determined pose a potential threat to the agricultural productivity and environmental values of the lands of Colorado. It is for advisory and education purposes only and is intended to encourage the collection of information needed to determine if the species should be listed as a noxious weed. 2.3 Garfield County Noxious Weed Management Garfield County adopted a Noxious Weed Management Plan in 2016 to limit the impact of noxious weeds by providing guidelines for managing designated noxious weeds which represent a threat to the continued economic, environmental , and agricultural value of lands in Garfield County (Garfield County 2016). Of the 7 7 plant species considered noxious by the State of Colorado, Garfield County is home to 40 species on this list. The plan provides for the implementation of the Colorado Noxious Weed Act by detailing integrated management options for designated noxious weeds. Options include education, preventive measures, good stewardship, and control techniques. August 2024 Page 3 The intent of the plan is to incorporate th e above-mentioned options that are the least environmentally damaging and are practical, timely and economically feasible. It is the responsibility of all landowners to use integrated methods to manage noxious weeds, and the responsibility of local governing bodies to ensu re that these plants are managed on public and private lands. Garfield County follows the dictates of the CDOAs rules as to which species on the A and B lists must be eradicated, contained , or suppressed and manages those species and the species on its own locally designated list in accordance with the Weed Management Plan . Section 3. Noxious Weed Survey Method s On July 24, 2024, HDR conducted pre-construction noxious weed surveys of the Murray and McLin Yard s, hereafter referred to as the study area to document baseline conditions . Noxious weed surveys were conducted using pedestrian transects, with approximately 50-foot separation, covering the entirety of the two staging yards . For the survey, the term “noxious weed ” includes species listed as noxious by the Colorado Department of Agriculture (CDOA 202 4a). Plant nomenclature for noxious weeds in this report follow the CDOA website . Before field surveys were conducted, the following data sources were reviewed for information on vegetation patterns, topography, and hydrology in the project vicinity: • Aerial Imagery – Recent and historic imagery from 1993 through 2019. • Topographic map – U.S. Geological Survey. • General ecological description of the project area (USDA -NRCS 2022). • National Land Cover Database (NLCD) Land Cover (USGS 202 4). • Colorado Department of Transportation (CDOT ) Noxious Weed Map (CDOT 202 4). • Colorado Natural Heritage Program (CNHP) Noxious Weed Inventory, Mapping, and Monitoring (CNHP 20 16). • Colorado Department of Agriculture’s (CDOA) noxious weed list (Effective October 2020) (CDOA 2024a). • CDOA County Weed Programs (CDOA 202 4b). Using ESRI ArcGIS Field Maps field collection software and a sub-foot geographic positioning system (GPS) technology using an EOSTM Arrow 100 antennae and receiver , noxious weed densities were recorded in four categories: 1-10 individuals, 11-100 individuals,101-999 individuals, and 1000+ individuals. Following the field survey, the spatial data of noxious weed species and densities were illustrated in ArcGIS Pro 3.1.2 for the study area. August 2024 Page 4 Section 4. Study Area Description 4.1 Location The Murray Yard is approximately 36 acres in size and the McLin Yard is approximately 15 acres in size. The study area is found within the Silt, CO U.S. Geological Survey 7.5-minute quadrangle (2019). The approximate decimal degree coordinates for the center of the McLin Yard are 39.530407, -107.610966 and for the center of the Murray Yard are 39.525274, -107.679326 (datum is NAD 83). Please refer to Appendix B for a photolog of the study area. 4.2 Topography and Hydrology The study area is in northwestern Colorado and lies within the Western Range and Irrigated Region Land Resource Region (USDA-NRCS 2022) at an elevation of approximately 5,650 feet. The study area is generally located on barren and highly disturbed rangeland and/ or agricultural fields. The McLin Yard is located directly east of a riparian corridor, which contains Divide Creek as well as two irrigation ditches. However, the McLin Yard does not receive any irrigation from these sources as it is approximately 100 feet upslope from them. The Murray Yard appears to drain to the west into an unnamed drainage that flows into a series of irrigation ditches north of County Road 346. Any flow associated with the Divide Creek to the west of the McLin Yard as well as the unnamed drainage to the west of the Murray Yard eventually joins the Colorado River to the north of the study area. 4.3 Land Use Land uses within and around the study area include s agricultural, livestock grazing, rural residential, and industrial uses. Interstate 70, the Town of Silt, and the Colorado River are located immediately north of the study area. There is oil and gas development throughout the surrounding area. 4.4 Climate Annual precipitation in the study area averages 11.6 inches and annual snowfall is 38.5 inches. Rifle records average annual high temperatures of 64.3 degrees Fahrenheit (˚F) and an average low temperature of 31.2 ˚F (Western Regional Climate Center 20 24). 4.5 Vegetation and Habitat The study area is located within dry and disturbed grassland habitat . Both locations appeared to have been chemically treated for noxious weeds in the recent past with visible wilting observed during the July 2024 survey . Additionally, all observed vegetation appeared to be stressed from lack of irrigation and herbivory by dense grasshopper infestations, which made identification difficult. Species that occur within the McLin Yard include prickly lettuce (Lactuca serriola ), field brome (Bromus arvensis), western wheatgrass (Pascopyrum smithii), Canada horseweed (Erigeron cana densis), kochia (Bassia scoparia), crested wheatgrass (Agropyron cristatum ), smooth brome (Bromus inermis), yellow salsify (Tragopogon dubius), and an unknown mustard August 2024 Page 5 (Brassica sp.). Species that occur within the Murray Yard include big sagebrush (Artemisia tridentata), kochia, greasewood (Sarcobatus vermiculatus), prickly pear (Opuntia sp.), needle- and-thread grass (Hesperostipa comata ), winterfat (Ceratoides lanata ), rubber rabbitbrush (Ericameria nauseosa ), western wheatgrass, crested wheatgrass, Russian thistle (Salsola tragus), four -wing saltbush (Atriplex canescens), and an unknown mustard. Please refer to Appendix C for a consolidated list of plant species observed during the field visit. Section 5. Noxious Weed Survey Results Four listed noxious weed species were observed in the study area during the July 2024 survey. Two of the four noxious weed species documented in the study area are on the CDOA’s List B and two are on List C (Table 1 and Figures 2 & 3 in Appendix A). All observed vegetation appeared to be stressed from lack of irrigation and herbivory by dense grasshopper infestations, which made identification difficult. No new growth was observed aside from prickly lettuce (Lactuca serriola) and field bindweed (Convolvulus arvensis), which were observed within the McLin Yard. The Colorado Department of Agriculture has prepared fact sheets for most state-listed noxious weeds. They feature detailed descriptions and photographs of the plants, as well as integrated management for each species. Noxious weed fact sheets for the four documented listed species are found in Appendix D. Garfield County follows the state’s rules as to which species on Lists A and B must be eradicated, contained , or suppressed and manages those species and the species on its own locally designated list in accordance with the Garfield County Noxious Weed Management Plan (Garfield County 2016). CDOT’s Noxious Weed Map details the locations of List A, B, and C noxious weeds as they occur along the ROW (CDOT 2024). Russian olive (Elaeagnus angustifolia ), hoary cress (Lepidium draba), field bindweed, Russian knapweed (Rhaponticum repens), salt cedar (Tamarix chinensis), musk thistle (Carduus nutans), and Scotch thistle (Onopordum acanthium ) were all documented along the portion of I -70 to the north of the study area. Cheatgrass (Bromus tectorum ) was the most common species identified throughout both Staging Yards. Field bindweed was identified on the east side of the McLin Yard. Small amounts of musk thistle were identified on the northwest side of the Murray Yard. Russian knapweed was identified from the northeast corner down through the center of the Murray Yard . Cheatgrass and field bindweed are designated by the State of Colorado as a List C species and Russian knapweed and musk thistle are List B species. Table 1. Colorado State Noxious Weed Species Observed in the Project Study Area Scientific Name Common Name General Habitat State of CO List Garfield County List Observed in the Study Area Bromus tectorum Cheatgrass Open, upland List C No Yes August 2024 Page 6 areas Carduus nutans Musk thistle Open, upland areas List B Yes Yes Convolvulus arvensis Field bindweed Open, upland areas List C No Yes Rhaponticum repens Russian knapweed Open, upland areas List B Yes Yes Sources: CDOA 2024a; Garfield County 2016 Section 6. Noxious Weed Management Construction activities would expose soils in areas that have been previously disturbed and limited areas that have not been previously disturbed. This disturbance creates a potential for the introduction and spread of noxious weeds in the project area. Noxious weed species that occur in and adjacent to disturbed areas of the project have the potential to spread into areas impacted by use and construction of access roads for construction equipment and use of staging areas. The goal of this plan is to minimize the spread of noxious weeds due to the proposed project’s construction activities. By implementing measures intended to minimize the spread of noxious weeds during construction and minimizing the establishment of new noxious weed populations post construction, the proposed project should minimize new and help reduce existing noxious weed infestations. Xcel and its contractors work to minimize the use of chemicals that are harmful to beneficial insects in their vegetation management practices controlling shrubs, trees, and weed species within their rights-of -way and properties. This includes eliminating the use of neonicotinoids, a class of neuro -active insecticides, which have been found harmful to all invertebrate populations including bee populations and other native pollinators (Xcel Energy Undated). The study area is adjacent to rural residential developments, rangeland, oil and gas operations, and agricultural fields. Due to adjacent roadways and residential properties in the adjacent areas, noxious weed species are expected to continue spread ing throughout the area. Future construction and maintenance activities by Xcel and its contractors have the potential to expose soils creating a potential for the introduction and spread of noxious weeds in the project area. The grading work will be minimized by limiting the disturbance footprint and focus ing on access grading impacts to the uphill side of access routes. Equipment associated with the project activities that may be stored on the McLin and Murray Yards vary based on the pole type and construction approach. Equipment that may be stored or staged on the McLin and Murray Yards includes construction materials, mini -excavators, pick-up trucks, boom trucks, concrete trucks, and trailer puller reels. Weed management priorities are based on the threat noxious weed species found in the project area pose to the overall goal of maintaining the health of the ecosystem. Generally, List A species are the highest priority because they are often the most aggressive species with limited distribution. No species designated as a “List A” species in the Colorado Noxious Weed Act were August 2024 Page 7 identified. List B species are next priority and List C species are generally widespread and are not prioritized. The best technique for controlling most noxious weeds is an integrated approach of chemical, mechanical, and biological controls. Chemical control involves the application of one or more herbicides at the appropriate time of the year (all herbicides should be applied by a certified applicator according to the manufacturer’s directions). Mechanical control usually involves mowing, hand -pulling, or cutting. Biological control is the use of organisms (usually insects, but also livestock) that are deliberately introduced to an area to control weeds. 6.1 Noxious Weed Treatment Measures As part of the weed management program, the following measure s will be implemented to minimize the spread of noxious weeds during the construction activities, as well as during restoration and reclamation efforts until the closure of the Storm Water Management Plan (SWMP). Xcel’s noxious weed management contractor will implement noxious weed control measures in accordance with existing regulations and local requirements. Post-construction control measures can include one or more of the following methods (that may be implemented during restoration activities): • Treatment methods will be based on species-specific and area-specific conditions (e.g., proximity to water or riparian areas, agricultural areas, and time of year) with the Garfield County coordinator being notified prior to noxious weed eradication activities . If areas are not seeded until the following spring, because of weather or scheduling constraints, undesirable vegetation will be eradicated before seeding. • Mechanical methods rely on equipment that can be used to mow or disc weed populations. If such a method is used in areas to be restored, subsequent seeding will be conducted to re -establish a desirable vegetative cover that will stabilize the soils and slo w the potential re -invasion of noxious weeds. • Discing or other mechanical treatments, that would disturb the soil surface within native habitats, will be avoided in favor of an herbicide application, which is an effective means of reducing the size of noxious weed populations as well as preventing the establishment of new colonies. • Herbicide applications will be controlled to minimize the impacts on the surrounding vegetation. In areas of dense infestation, a broader application will be used and a follow - up seeding program will be implemented. Pre-Construction Prior to construction and soil disturbances, Xcel’s noxious weed contr actor shall apply pre - August 2024 Page 8 treatment, both chemical and mechanical to List A and List B noxious weeds in the areas of expected disturbance which includes staging yards, within expected access road disturbance areas, and any other areas identified in the grading permit as to be disturbed. Chemical and mechanical treatment will be in accordance with the specifics listed in Table 2 and until the SWMP is closed. Post-Construction - Phase 1 At the conclusion of construction (Year 1), disturbed areas will be inspected/surveyed for noxious weeds by a qualified weed specialist. The weed specialist will identify areas where the Control Techniques listed in Table 2 following measures shall be implemented. Post-Construction - Phase 2 Following the growing season after construction has been completed (Year 2) and until the project SWMP permit is closed , two noxious weed surveys shall occur yearly: 1. Early season (May-June) for cool-season noxious weeds (e.g., cheatgrass and bindweed). 2. Late season (July-August) for the warm-season noxious weeds (e.g., thistles and knapweeds). Areas of infestations identified in these surveys will determine appropriate treatment and suppression methods. Table 2 presents species-specific recommended control measures which may be implemented. These recommended control measures are from the Colorado Department of Agriculture website (CDOA 2024a). Some of the noxious weed species are widespread and not found in defined populations, therefore treatment will be difficult and may not be prioritized. Treatment will only occur in areas where soil disturbance due to construction occurred. Due to the knapweed plants being dead and dry during the July 2024 survey, identification should be confirmed based on new growth prior to any treatment measures being impl emented. Table 2. Noxious Weed Species Recommended Control Techniques Common Name Chemical Mechanical Biological Russian knapweed Aminopyralid (Milestone), Aminocyclopyrachlor + Chlorsulfuron (Perspective). Most effective if applied in the fall when above- ground stems die back . Cutting or mowing can stress plant and force it to use reserves. Tilling and disking can create root fragments that can sprout. However, repeated deep tillage (1 feet) over 3 years can kill much of the root system. The gall midge, Jaapiella ivannikovi, is a fly that lays eggs in the shoot tips of Russian knapweed. It forms galls that reduce flowering, seed production, and stunts the plants’ growth. This biocontrol will stress the stand of Russian knapweed but will not likely eliminate it. Not available to public. August 2024 Page 9 Downy brome (cheatgrass) Pseudomonas fluorescens D7 inhibits cheatgrass and is currently approved by EPA and Colorado. Mechanical methods are best for residential areas and small infestations. Collect, bag, and dispose of or destroy flowers; seeds can mature and germinate if left. Tilling must be deeper than 6 inches to work. Prescribed fire applied before seed maturity, (late spring or early summer), may kill seeds; the trick is to get green cheatgrass and litter to carry fire and at a hot enough temperature to destroy seeds and seedlings. No approved biological control agents . Musk thistle Aminopyralid (Milestone), Chlorsulfuron (Telar), and Clopyralid (Transline). Apply in spring from rosette through very early flower growth stages. Methods, such as tilling, hoeing and digging, are best for infestations smaller than 0.5 acres. Sever roots below the soil surface during the first year before the plant stores energy, and in the second year before flower production. Mowing, chopping and d eadheading stimulates more flower production; these methods require consecutive years of season-long treatments. All flower buds and heads must be collected, bagged, and disposed of or destroyed. Prescribed fire that results in high soil burn severity damages roots and above ground biomass, but is not recommended due to impacts on desired plants. Trichosirocalus horridus is the only biological control agent available for musk thistle in Colorado. Field bindweed Clarity + 2,4-D Amine, Tordon 22K *this is a Restricted Use Pesticide, and Roundup Ultra *non- selective herbicide, will kill all vegetation* See Application timing on Noxious Weed Fact Sheets. Cutting, mowing, or pulling has a negligible effect unless the plants are cut below the surface in the early seedling stage. The bindweed gall mite, Aceria mahlerbae, has proven to be effective in reducing field bindweed infestations. Source: Colorado Department of Agriculture (2024a). Table 2 - Control Techniques based on recommendation f rom Garfield County Weed Control Manager, Steve Anthony following the CDOA-published control techniques for noxious weeds . Section 7. Recommended Management and Mitigation Actions In addition to the specific management recommendations listed for each species in Table 2, the following mitigation measures are recommended (as appropriate) to minimize the spread of noxious weeds: August 2024 Page 10 • Construction equipment will remain in designated work areas . • The area of ground disturbance will be kept to the minimum necessary. • Minimize imported topsoil during construction. If importing is necessary, use certified weed-free soil. • Equipment will be thoroughly cleaned before entering the staging area, if equipment or trailer are carrying soil or plant materi al, i.e. mud on trailer undercarriage . • Mulches and straw used at the site will be certified weed -free. • Disturbed areas will be seeded after construction though, if the root structure remains intact, contractor may decide to not seed in such areas. • Seed mixes, soil, and other plant material used for revegetation will be free of noxious weed seeds, roots, and other propagules. • Only a Colorado -licensed Supervisor or Certified Operator will apply herbicides. • Herbicides will be applied in accordance with the manufacturer’s instructions. • Broadcast herbicide spraying will be limited to areas of project ground disturbance and at staging areas. • The Garfield County Vegetation Manager will be notified prior to noxious week treatments, as appropriate to the disturbance jurisdiction. At time of the memorandum, this notification would be through the Garfield County Vegetation Manager (Steve Anthony – 970-945-1377 ext. 4305, santhony@garfield -county.com). • Applicable best management practices (BMPs) from the Stormwater Management Plan will be implemented. Section 8. References Colorado Department of Agriculture (CDOA). 202 4a. Noxious Weeds. Available online: https://www.colorado.gov/pacific/agconservation/noxiousweeds and https://drive.google.com/file/d/0Bxn6NtpJWc9JRFE3LW1RWFVXY1E/view?resourcekey=0 -WalETB5Qp3zCjfRnar5t3g . Accessed July 2024. CDOA. 2024b. County Weed Programs. Available online: <https://ag.colorado.gov/conservation/noxious -weeds/county-weed-programs>. Accessed July 2024. Colorado Department of Transportation (CDOT). 202 4. Noxious Weeds Map. Available online: https://cdot.maps.arcgis.com/home/webmap/viewer.html?webmap=ebd39c7a542349c6914 89f5ecb1a1c62#!. Accessed July 2024. Colorado Natural Heritage Program (CNHP). 2016. Survey of Critical Biological Resources: a resurvey and update of Potential Conservation Areas in Garfield County, Colorado. Available online: https://cnhp.colostate.edu/wp - content/uploads/download/documents/2016/Final_Garfield_2016_report.pdf . Accessed July 2024. August 2024 Page 11 Garfield County. 2016. Garfield County Noxious Weed Management Plan. Available online: https://www.garfield -county.com/vegetation - management/filesgcco/sites/29/2019/11/Garfield -County-Noxious-Weed-Management- Plan-Adopted-Feb-2016.pdf . Accessed July 2024. U.S. Department of Agriculture (USDA)- Natural Resources Conservation Service (NRCS). 2022. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. Natural Resources Conservation Service, USDA Handbook 296. U.S. Geological Survey (USGS). 202 4. National Land Cover Database (NLCD). Available online: https://apps.nationalmap.gov/viewer/. Accessed July 2024 . Western Regional Climate Center. 202 4. Climate Summaries. Available online: https://wrcc.dri.edu/Climate/summaries.php . Accessed July 2024. Xcel Energy. Undated. Wildlife and Habitat Protection. Available online: https://www.xcelenergy.com/staticfiles/xe - responsive/Company/Corporate%20Responsibility%20Report/2019%20CRR/2019_Wildlife %20and%20Habitat%20Protection_CRR.pdf . Accessed July 2024. Appendix A. Figures Appendix B Appendix B. Representative Photographs Appendix B Photo 1 Date Taken: July 2024 Bare ground mixed with dead and stressed vegetation on the west side of the McLin Yard. Photo 2 Date Taken: July 2024 Field bindweed (Convolvulus arvensis ) on the east side of the McLin Yard. There appeared to be evidence of chemical weed treatment along roadways and where field bindweed was identified. Photo 3 Date Taken: July 2024 Mosaic of field brome (Bromus arvesis), cheatgrass (Bromus tectorum ), and an unknown mustard throughout the McLin Yard. Note the dried state of all vegetation, which made identification difficult. Appendix B Photo 4 Date Taken: July 2024 Dead big sagebrush (Artemesia tridentata) and stressed vegetation on the north side of the Murray Yard. Photo 5 Date Taken: July 2024 Dead Russian knapweed (Rhaponticum repens) in the northeast corner of the Murray Yard. Photo 6 Date Taken: July 2024 Mix of big sagebrush, cheatgrass, and needle-and-thread grass (Hesperostipa comata) on the south side of the Murray Yard. Appendix C Plant List Appendix C Plant Species Observed in the Project Survey Area During the July 2024 F ield Survey Scientific Name Common Name Noxious weed Indicator* Agropyron cristatum Crested wheatgrass - Artemisia tridentata Big sagebrush - Atriplex canescens Four-wing saltbush - Bassia scoparia Kochia - Brassica sp. Mustard - Bromus arvensis Field brome - Bromus inermis Smooth brome - Bromus tectorum Cheatgrass C Carduus nutans Musk thistle B Ceratoides lanata Winterfat - Convolvulus arvensis Field bindweed C Ericameria nauseosa Rubber rabbitbrush - Erigeron canadensis Horseweed - Hesperostipa comata Needle-and-thread grass - Lactuca serriola Prickly lettuce - Opuntia sp. Prickly pear - Pascopyrum smithii Western wheatgrass - Rhaponticum repens Russian knapweed B Rhus aromatica Fragrant sumac - Sarcobatus vermiculatus Greasewood - Salsola tragus Russian thistle - Tragopogon dubius Yellow salsify - *Source: Colorado Department of Agriculture (202 4a). Appendix D. Noxious Weed Fact Sheets List C Key ID Points 1. Downy leaf blades, sheaths, ligules 2. Glumes are unequal size, lemmas are downy 3. One-sided panicle that droops, red-purple during seed set & senescence 4. Fibrous roots C heatgrass (Bromus tectorum L.) is a winter annual grass in the Poaceae family, also known as downy brome. Mature plants reach up to 24 inches tall. The stems are smooth but the leaf blades and sheath are hairy (downy). The ligules are fringed, short and membra- nous. The culms range from five to 90 cm long, can be prostrate or vertical, and have fine short hairs. Its fibrous roots can be up to 60 inches long, but the majority of root biomass is within first 12 inches of the soil surface. Roots are efficient at absorbing soil moisture, allowing cheatgrass to grow quickly early in season, while other plants are still dormant. Green up can occur twice per season. Cheatgrass has an unique spectral signature during seed set and senescence when it turns reddish purple. During these shoulder growing season events, it is easily detectable from other vegetation with satellite imagery. The flower is a simple one-sided panicle that characteristically flops over and hangs, branches and is open. Spikelets are usually terminal. Usually there are five to many florets; it has perfect flow- ers. The upper and lower glumes are usu- ally unequal in length and shorter than florets; the lower glume ranges from 4 to 14 mm in length and is one veined. The upper glume is three-veined. The plant disarticulates above the glumes. The lemmas are usually downy, narrowly lanceolate with sharp tips and about 9 to 12 mm long. Usually there are five to many lemmas. Awns are usually pres- ent and range from 10 to 18 mm long. It is a prolific seed producer, capable of two seed crops per season. Seeds need to be buried in soil or litter and have fall moisture to germinate. The fall seed crop has greater reproductive success than spring. Seeds lack dispersal anatomy so fall close to parent plants but transport readily with animals, people and equip- ment. Seed longevity is about three years. Both inbreeding and cross breed- ing occur. Cheatgrass is one of the most com- petitive non-natives in the Western US. It thrives in arid, semi arid, and cold environments. Colorado’s high eleva- tion range is not an issue for cheatgrass; plants were recently detected as high as 9,500 feet. It exhibits phenotypic plastic- ity and genetic diversity, making it high- ly adaptable to a variety of conditions, likely due to multiple introductions. Its presence has significant negative impacts throughout the West. Most no- tably, it alters fire regimes and thus engineers a posi- tive fire feedback loop that favors its growth over other plants. This feedback loop is why cheatgrass forms monocultures throughout the West. It is often confused with Japanese brome (Bromus ja- ponicus), which has denser more compact spikelets, shorter awns, and changes from green to gold through the growing season. Ch e a t g r a s s Br o m u s t e c t o r u m L . Cheatgrass Identification and Management © Leslie J. Mehrhoff, University of CT © Veronika Johansson, iNaturalist © Priyantha Wijesinghe, iNaturalist ©James Bailey, iNaturalist Rev. 2/19 Colorado Department of Agriculture - Conservation Services 305 Interlocken Parkway Broomfield, CO 80021 (303) 869-9030 www.colorado.gov/ag/weeds List C Ch e a t g r a s s Br o m u s t e c t o r u m L . Integrated Weed Management Recommendations Effective integrated management means using a variety of eradication methods in the same site along with restoration, prevention of seed production and dispersal, and monitoring. Maintain robust healthy native landscapes. Restore degraded sites. Avoid soil disturbance. Prevent seed production and seed dispersal, e.g. on contaminated equipment. Rest sites until restored. Modify land use practices. Use methods appropriate for the site, including land use practices. MECHANICAL Mechanical methods are best for residential areas and small infestations. Mowing and chopping are not recommeded; they leave roots behind, stimulate flower production, disperse seeds, and expand the size of the infested area. Collect, bag, and dispose of or destroy flowers; seeds can mature and germinate if left. Tilling must be deeper than 6 inches to work. Prescribed fire applied before seed maturity, (late spring or early summer), may kill seeds; the trick is to get green cheatgrass and litter to carry fire and at a hot enough temperature to destroy seeds and seedlings. Always combine prescribed fire with cultural methods, timed appropriately, and base it on site conditions and other plants present. Monitoring and adaptive management are critical if prescribed fire is used as a tool for control. CHEMICAL Pseudomonas fluorescens D7 inhibits cheatgrass and is currently approved by EPA and Colorado. NOTE: Herbicide recommendations to control cheatgrass in pastures and rangeland are found at: https://goo.gl/ TvWnv9. Rates are approximate and based on equipment with an output of 30 gal/acre. Follow the label for exact rates. Consult local turf and ornamental experts for residential settings. Always read, understand, and follow the label directions. The herbicide label is the LAW! BIOLOGICAL Sheep and cattle will select green cheatgrass which also affects desired cool-season grasses. Properly managed grazing can improve vigor of desired species and directly reduce cheatgrass. Post-fire grazing management varies depending on site potential and objectives. Currently there are no biological control agents for cheatgrass authorized in Colorado. For more biocontrol information, visit the Colorado Department of Agriculture’s Palisade Insectary website at: www.colorado.gov/ag/biocontrol CULTURAL Biological soil crust is a soil health indicator of arid and semi arid sites; crusts inhibit cheatgrass seed germination. Aerial spread and cultivate soil crust where it is absent. Aerial and drill seeding bluebunch wheatgrass (Pseudoroegneria spicata) and Sandberg bluegrass (Poa secunda) with vesicular-arbuscular mycorrhizae; these are drought tolerant natives that are highly competitive against cheatgrass but require mycorrhizae. As these grasses establish and cheatgrass wanes slowly introduce additional species such as thickspike wheatgrass (Elymus lanceolatus), winterfat (Krascheninnikovia lanata), yarrow (Achillea millefolium) in the plant interspaces in subsequent years. Be cautious when purchasing seed as cheatgrass is often a contaminate, especially in mixes. Use seed pillows to disperse seeds. © Stacy Litz, Associated Press © Bureau of Land Management© Martin Bernetti, Associated Press © Helena Weed Control, Rocky Mountain Elk Foundation White flower © Mary Ellen Harte, Invasive.org. All other photos © Kelly Uhing. F i e l d b i n d w e e d Leaves are shaped like ar- rowheads. Flowers are funnel-shaped, white to pink, and have two small bracts one inch below the flower base. 1. 2. Identification and Impacts F ield bindweed (Convolvulus arvensis) is a non-native deep- rooted perennial that reproduces from seed and creeping, horizontal roots (rhizomes). Field bindweed stems are prostrate (grows low to the ground) and twining, and grow up to 6 feet long. Leaves are distinguishable by their arrowhead shape. The flowers are bell or trumpet-shaped, white to pink in color, and are about 1 inch long. Field bindweed seeds can remain viable in the soil for up to 40 years. F ield bindweed emerges from its root system in the spring. Flowering occurs from June to September and until the first fall frost. The number of seeds produced per plant ranges from 25 to 300 and seed production is variable depending on environmental conditions. Field bindweed is an extremely difficult noxious weed to control because, in part, of its taproot that may go 20 feet deep into the soil, and which repeatedly gives rise to numerous long rhizomes. F ield bindweed is a problem throughout Colorado. It is one of the most competitive perennial weeds. It is widespread in cultivated areas, pastures, lawns, gardens, roadsides, and waste areas from 4,000 to 8,000 Key ID Points C o n v u l v u l u s a r v e n s i s Field bindweed Identification and Management feet in elevation. T o successfully manage field bindweed, containment and persistence in controlling existing stands are necessary in order to exhaust the root system and deplete the soil seed bank. This weed needs to be continually stressed, forcing it to exhaust root nutrient stores and eventually die. Of all control methods, prevention is most important. Maintain healthy pastures and rangeland and continually monitor your property for new infestations. A healthy cover of desirable perennial plants will assist in discouraging field bindweed establishment. F ield bindweed is designated as a “List C” species on the Colorado Noxious Weed Act. It is required to be either eradicated, contained, or suppressed depending on the local jursidictions managing this species. O n the back of this sheet are field bindweed management recommendations. For more information, visit www.ag.state. co.us/csd/csdhome.html. Or call the State Weed Coordinator at the Colorado Department of Agriculture, Conservation Services Division, 303- 239-4100. List C Species Rangeland, pasture, and riparian site recommendations List C Species CULTURAL Establishment of selected grasses can be an effective cultural control of field bindweed. Contact your local Natural Resources Conservation Service for seed mix recommendations. Maintain healthy pastures and prevent bare spots caused by overgrazing. Bareground is prime habitat for weed invasions. BIOLOGICAL The bindweed gall mite, Aceria mahlerbae, has proven to be effective in reducing field bindweed infestations. This is an option for large infestations. To obtain a mite release, contact the Colorado Department of Agriculture, 970-464-7916. MECHANICAL Cutting, mowing, or pulling has a negligible effect unless the plants are cut below the surface in the early seedling stage. Well-established populations have a large seed bank in the soil that can remain viable for over 40 years. Bindweed mite damage F i e l d b i n d w e e d Integrated Weed Management: Field bindweed requires active management once it is established because of its potential to regenerate rapidly. Even small infestations should be viewed as a serious threat and managed aggressively. Contain and persistently control infestations in order to exhaust the root system and deplete the soil seed bank. Maintain a healthy cover of perennial plants to discourage field bindweed establishment. ht t p : / / w w w . a g . s t a t e . c o . u s / c s d / c s d h o m e . h t m l HERBICIDES : The following are recommendations for herbicides that can be applied to range and pasturelands. Rates are approximate and based on equipment with an output of 30 gallons per acre. Please read label for exact rates. Always read, understand, and follow the label directions. The herbi - cide label is the LAW! M a n a g e m e n t R e c o m e n d a t i o n s HERBICIDE RATE APPLICATION TIMING Clarity + 2,4-D Amine 1 qt./acre or 1 oz/gal water Just after full-bloom and/or fall. DO NOT apply near or under trees/shrubs or where soils have rapid permeability. DO NOT apply when outside temperatures will exceed 85 degrees. Add non-ionic surfactant @ 0.32oz/gal water or 1 qt/100 gal water. Tordon 22K *this is a Restricted Use Pesticide* 1 qt./acre or 1 oz/gal water Just after full-bloom and/or fall. DO NOT apply near or under trees/shrubs or where soils have rapid permeability. Add non-ionic surfactant @ 0.32oz/gal water or 1qt/100 gal water. Roundup Ultra *non-selective herbicide, will kill all vegetation* 4 - 5 qts./acre or 4 - 5 oz/gal water Apply at full-bloom and/or fall. Add non-ionic surfactant @ 0.32oz/gal water or 1qt/100 gal water. Use caution when applying near grasses or other desirable vegetation. Integrated Weed Management recommendations List C Species List B Key ID Points 1. Leaf with white midrib and leaf margins with spines. 2. Pappus with plumose barbed bristles. 3. Wide, stout lance-shaped bracts with spiny tips. M usk thistle Carduus nutans L. is a non-native biennial forb that re- produces solely by seed. During the first year of growth, a rosette forms in spring or fall. During the second year in mid to late spring, the stem bolts, flowers, sets seed, and the plant dies. M usk thistle can grow up to 6 feet tall. The leaves have spines, are waxy, and dark green in color with a prominent light green to white midrib that can be seen from a distance. Leaves are dentately lobed; leaf bases some- times extend down below the point of attachment. The terminal flower heads are purple, large in size (1.5 to 3 inches in diameter) and bend over as if nod- ding. These flower heads are made up of only disk flowers. They are surrounded by numerous, wide and stout lance- shaped, spine-tipped bracts that resem- ble an open pineapple. The pappus has plumose bristles that appear barbed un- der magnification. Musk thistle produces many flower heads. The tallest shoots flower first; lateral shoots develop in leaf axils. A robust plant may produce 100 or more flowering heads. Reproduction is usually via out-crossing through insect pollination, but self-pollination also occurs. Flowers emerge in May through September. Seeds develop shortly after flowers emerge. Flower buds can contain viable seeds from self-pollination. Seeds can mature on severed bud and flower- heads. Seeds remain viable in the soil for up to about 14 years. Seeds can germi- nate and emerge from spring through fall. M usk thistle habitat is found in a variety of environments extend- ing from shortgrass prairie to alpine. It is strongly associated with heavily disturbed sites, where over-use occurs or where site conditions are poor due to land management practices. This includes over-grazed areas, large fires, trails, ditches and roadsides. Infested livestock pasturs suffer from significantly decreased carrying capacity. B ecause musk thistle reproduces solely from seed, the key for suc- cessful management is to prevent seed production. Once flowers emerge and start to produce seed, effective manage- ment options will become limited. Once sites are infested, musk thistle can form dense stands. Prevention, adjusting land management practices, a robust inte- grated treatment plan and restoration are critical to eliminating this species. M usk thistle is designat- ed as a “List B” species in the Colorado Noxious Weed Act. It is required to be eradicated; some popu- lations may be contained or suppressed depending on state regulations. For management directions for each county, refer to the most recent Rule, or visit www.colorado.gov/ag/co- weedcontacts for details. Mu s k t h i s t l e Ca r d u u s n u t a n s L. Musk Thistle Identification and Management 2015 Quarter Quad Survey © Chris Evans, University of IL © Bruce Ackley, OH State University © Les Mehrhoff, DiscoverLife.org Rev. 11/16 Colorado Department of Agriculture - Conservation Services 305 Interlocken Parkway Broomfield, CO 80021 (303) 869-9030 www.colorado.gov/ag/weeds List B Effective integrated management means using a variety of eradication methods that also includes restoration, prevention of seed production and dispersal, and monitoring. Maintain robust healthy native landscapes and restore degraded sites. Avoid soil disturbance. As with most biennials, prevent seed production in the first and second year of musk thistle growth. Prevent seed from dispersing, such as on contaminated equipment. Rest sites until they are effectively restored. Change land use practices. Use methods appropriate for the site. Mu s k t h i s t l e Ca r d u u s n u t a n s L. Integrated Weed Management Recommendations HERBICIDE RATE APPLICATION TIMING Aminopyralid* (Milestone)6 oz./acre + 0.25% v/v non-ionic surfactant Apply in spring rosette to early bolting growth stages or in fall to rosettes. *Product not permitted for use in the San Luis Valley. Chlorsulfuron** (Telar)1-2.6 oz. product/acre + 0.25% v/v non-ionic surfactant Apply in spring from rosette through very early flower growth stages. (Can prevent viable seed formation if applied no later than the first viable flowers begin to open.) **This herbicide has residual soil activity that will affect all broadleaf seedlings germinating after application has occurred. Clopyralid (Transline)0.67-1.33 pints product/acre + 0.25% v/v non-ionic surfactant Apply to rosettes through flower bud stage in spring, or to fall rosettes. © Friends of NV Wilderness Stewardship Team MECHANICAL CONTROL METHODS Methods, such as tilling, hoeing and digging, are best for infestations smaller than 0.5 acres; weigh this against other plants present, ecology and site condition. Sever roots below the soil surface during the first year before the plant stores energy, and in the second year before flower production. Mowing, chopping and deadheading stimulates more flower production; these methods require consecutive years of season-long treatments. All flowerbuds and heads must be collected, bagged, and disposed of or destroyed; seeds will mature and germinate if left on the ground. Prescribed fire that results in high soil burn severity damage roots and above ground biomass, but is not recommended due to impacts on desired plants. Fire generally favors musk thistle germination. BIOLOGICAL CONTROL METHODS Although horses, cattle, goats and sheep may eat flower heads on a few plants, seeds pass through their digestive tracks unaltered and spread. The leaf and stalk spines can cause domestic livestock to avoid mature musk thistle. Thus, musk thistle can become an “increaser” in over-grazed systems. Properly managed grazing can improve vigor of desired species and indireclty reduce musk thistle. Trichosirocalus horridus is the only biological control agent available for musk thistle in Colorado. The other species, Rhinocyllus conicus, is not host specific and will damage native thistles, and therefore cannot be released as an agent in Colorado. For more information, visit the Colorado Department of Agriculture’s Palisade Insectary website at www.colorado.gov/ag/biocontrol. CULTURAL CONTROL METHODS Musk thistle is not tolerant of competition and needs light to germinate seeds. Cultural methods should aim to maintain or restore a competitive assemblage of forbs, cool and warm season grasses. Implement whole site restoration of soils, plants and water regimes where stands of musk thistle exist where needed. Use locally adapted species that are ecologically appropriate for the site to improve competitiveness. Include annual as well as perennial species. Incorporate soil amendments, soil microbes and mycorrhizal fungi in restoration and land management efforts. Minimize soil compaction and disturbance, especially in wetlands and moist soil. Irrigation can increase competitive species. CHEMICAL NOTE: The following are recommendations for herbicides that can be applied to pastures and rangeland. Rates are approximate and based on equipment with an output of 30 gal/acre. Follow the label for exact rates. Always read, understand, and follow the label directions. The herbicide label is the LAW! © Eric Coombs, OR Dept of Agriculture © Norman E. Rees, USDA Ag Research Service List B ,yBlacBlacBlacBlacBlacBlaBlacBlacBlacacBlacBlBlacBBlacBlacaaccacaksk, sk, sk, sk, sk, sk, sk, sk, sk, sk, sk, sk, skkskcalycalycalycalycalycalyalycalycalycalyalyaalalyalal rooroorooooroorooroorooroooooortttttttttttt yyyyyyy© St© St© St©S eveeveeveeveeeeeeeee DeweDeweDeweDewey USy USy USy USUUUU Key ID Points 1. Distinguished from other knapweeds by the flower’s smooth, papery bracts. 2. Roots are brown to black with scaly appearance. 3. Rosettes and lower leaves deeply lobed. 4. Upper leaves are smaller, smooth margined, and not lobed. Russian knapweed (Acroptilon repens) is a non-native, deep-rooted perennial that spreads by aggressive, creeping, horizontal roots (rhizomes) and seeds. The roots are brown to black with a scaly appearance. Russian knapweed can grow up to 3 feet in height. The stems and leaves are covered with short gray hairs. The ƪǦǡ in color, and are solitary at the tips of the upper branches. Russian knapweed can be distinguished from other knapweeds by the smooth, papery, rounded bracts that surround the ƪǤ in early spring after soil temperatures remain above freezing. It produces ƪ seed in late summer to early fall. The seeds are viable for two to three years. Russian knapweed reproduces primarily from its root system. Buds on the horizontal roots can form adventitious ǡǡ that can grow to become independent plants. Once rosettes emerge in the ǡǦơ until they develop again in late summer. ǡ develop into new plants. Russian knapweed is allelopathic, which means it contains a toxic substance that inhibits the growth of competing plants. This weed may also be toxic to horses resulting in serious injury or possibly death of the animal. Russian knapweed displaces native vegetation and reduces forage values on range and pasturelands. Habitat for Russian knapweed includes roadsides, ditch banks, riparian zones, pastures, rangeland, saline soils, clear cuts, and cropland. It typically invades degraded areas and sites with full sun. Tơ for Russian knapweed is to prevent its establishment through proper land management. Maintain healthy pastures and rangeland and continually monitor your property for new infestations. If Russian knapweed is already established, using an integrated weed management approach proves to ơ Ǥ managed with herbicides or biocontrol insects, but long-term control must include planting competitive plant species to occupy bare ground once infested by the weed. Details on the back of this sheet can help to create a management plan compatible with your site ecology. R ussian knapweed is designated as a “List B” species in the Colorado Ǥ is required to be either eliminated, contained, or suppressed depending on the local infestations. For more information, visit www.colorado.gov/ag/ weeds and click on the Noxious Weed Program link or call the State Weed Coordinator at the Colorado Department of ǡ Services Division, ͵Ͳ͵ǦͺͻǦͻͲ͵ͲǤ Ru s s i a n k n a p w e e d Ac r o p t i l o n r e p e n s Ƥ 2008 Quarter Quad Survey Colorado Department of Agriculture - Conservation Services 305 Interlocken Parkway Ƥǡ͔͔͖͕͜ ȋ͔͗͗Ȍ͚͜͝Ǧ͔͔͗͝ Ǥ ǤȀȀ List B ơ Ǥ ơ Ǥ ǡǦ Ǥ Ru s s i a n k n a p w e e d Ac r o p t i l o n r e p e n s HERBICIDE (Milestone) 5-7 oz/acre Ǧ buds are highly susceptible; can also apply in the bud to senes- ǤǦ ̷͔Ǥ͖͗Ȁ ͕Ȁ͕͔͔Ǥ - clopyrachlor + chlorsulfuron (Perspective) 4.75 to 8 oz ȀΪ adjuvant Ǧ buds are highly susceptible; can also apply in the bud to se- Ǥ ǣ ͙Ǥ͙ Ȁ Ǥ the root zone of desirable trees and shrubs. Picloram (Tordon 22K *this is a Restricted Use Pesticide*) 1 qt/acre or 1 oz/gal water Ǧ buds are highly susceptible; can also apply in spring to bud/early ȀǤǦ ̷ ͔Ǥ͖͗Ȁ͕Ȁ͕͔͔Ǥ The following are recommendations for herbicides that can be Ǥǡǡ follow the label directions. Please read label for exact rates. The Ǩ Mowing several times before the plants bolt stresses Russian knapweed and forces it to use nutrient reserves stored in the root system. However, mowing alone will not eliminate the infestation and it can stimulate shoot sprouting the following year. Mowing combined with a fall herbicide application will enhance control. Tilling and disking can create root fragments that can sprout. However, repeated deep tillage (1 feet) over 3 years can kill much of the root system. The gall midge, Jaapiella ivannikoviǡƪ shoot tips of Russian knapweed. It forms galls that reduce ƪǡ ǡǯǤ biocontrol will stress the stand of Russian knapweed but will Ǥ Ǧ ǡͻͲǦͶͶǦͻͳǡ biocontrol . It is not yet available to the public. Maintain healthy pastures and prevent bare spots caused by overgrazing. Bare ground is prime habitat for weed invasions. Establishing sod-forming grasses or vegetation with dense shade ơ Ǥ your local Natural Resources Conservation Service for seed mix recommendations.