Noxious weeds are plants that are considered harmful to animals or the environment, typically (but not always) nonnative species, which spread rapidly at the expense of native vegetation.
There are many species of exotic and invasive weeds in the Utah. Some species, however, have more potential to be “injurious to public health, crops, livestock, land, or other property” [1]. The Utah Noxious Weed Act of 2008 had defined 28 noxious weed species into three prioritization categories. In December 2015 the official State Noxious Weed list was updated to include 54 species and prioritization categories were modified as follows:
Class 1A: Early Detection Rapid Response (EDRR) watch list
Declared noxious weeds and invasive weeds that are not native to the State of Utah, are not known to exist in the state but pose a serious threat, and should be considered a very high priority.
Common crupina Crupina vulgaris | Syrian bean caper Zygophyllum fabago |
African rue Peganum harmala | Ventenata (North Africa grass) Ventenata dubia |
Small bugloss Anchusa arvensis | Plumeless thistle Carduus acanthoides |
Mediterranean sage Salvia aethiopis | Malta starthistle Centaurea melitensis |
Spring millet Milium vernale |
Class 1B : EDRR
Declared noxious and invasive weeds not native to the State of Utah that are known to exist in the state in very limited populations, pose a serious threat to the state, and should be considered as a very high priority.
Camelthorn Alhagi maurorum | Japanese knotweed Polygonum cuspidatum |
Garlic mustard Alliaria petiolata | Blueweed (Viper's bugloss) Echium vulgare |
Purple starthistle Centaurea calcitrapa | Elongated mustard Brassica elongata |
Goatsrue Galega officinalis | Common St. Johnswort Hypericum perforatum |
African mustard Brassica tournefortii | Oxeye daisy Leucanthemum vulgare |
Giant reed Arundo donax | Cutleaf viper grass Scorzonera laciniata |
Class 2: Control
Declared noxious and invasive weeds not native to the State of Utah that pose a threat to the state and should be considered a high priority for control. Weeds listed in the control list are known to exist in varying populations throughout the state. The concentration of these weeds are at levels for which control or eradication may be possible.
Leafy spurge Euphorbia esula | Dyers woad Isatis tinctoria |
Medusahead Taeniatherum caput-medusae | Yellow starthistle Centaurea solstitialis |
Rush skeletonweed Chondrilla juncea | Yellow toadflax Linaria vulgaris |
Spotted knapweed Centaurea stoebe | Diffuse knapweed Centaurea diffusa |
Purple loosestrife Lythrum salicaria | Black henbane Hyoscyamus niger |
Squarrose knapweed Centaurea virgata | Dalmatian toadflax Linaria dalmatica |
Class 3: Containment
Declared noxious and invasive weeds not native to the State of Utah that are widely spread. Weeds listed in the containment noxious weeds list are known to exist in various populations throughout the state. Weed control efforts may be directed at reducing or eliminating new or expanding weed populations. Known and established weed populations, as determined by the weed control authority, may be managed by any approved weed control methodology, as determined by the weed control authority. These weeds pose a threat to the agricultural industry and agricultural products.
*Bermudagrass (Cynodon dactylon) shall not be a noxious weed in Washington County and shall not be subject to provisions of the Utah Noxious Weed Law within the boundaries of that county. | |
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Russian knapweed Acroptilon repens | Musk thistle Carduus nutans |
Houndstounge Cynoglossum officinale | Quackgrass Elymus repens |
Perennial pepperweed (Tall whitetop) Lepidium latifolium | Jointed goatgrass Aegilops cylindrica |
Phragmites (Common reed) Phragmites australis ssp. | Bermudagrass* Cynodon dactylon |
Tamarisk(Saltcedar) Tamarix ramosissima | Perennial Sorghum spp. Sorghum halepense Sorghum almum |
Hoary cress Cardaria spp. | Scotch thistle (Cotton thistle) Onopordum acanthium |
Canada thistle Cirsium arvense | Field bindweed (Wild Morning-glory) Convolvulus spp. |
Poison hemlock Conium maculatum | Puncturevine (Goathead) Tribulus terrestris |
Class 4: Prohibited
Declared noxious and invasive weeds, not native to the State of Utah, that pose a threat to the state through the retail sale or propagation in the nursery and greenhouse industry. Prohibited noxious weeds are annual, biennial, or perennial plants that have the potential or are known to be detrimental to human or animal health, the environment, public roads, crops, or other property.
Cogongrass (Japanese blood grass) Imperata cylindrica | Scotch broom Cytisus scoparius |
Myrtle spurge Euphorbia myrsinites | Russian olive Elaeagnus angustifolia |
Dames Rocket Hesperis matronalis |
State land managers, local governments, and property owners are responsible for controlling weed species found on the state’s noxious weeds list, and local weed species of concern, if necessary. Weed control responsibilities extend to lands under local management (roads, right-of-ways, parks, etc.) as well as enforcing provisions of the Utah Noxious Weed Act on private lands. If landowners are unwilling or unable to address weed problems on their own land, state law provides county weed managers the right to treat weeds on private lands (assuming proper notice is provided) and subsequently seek reimbursement or apply liens for the work.
For the SEUALG region, there are county, state, and federal goals identified in respective planning documents. In general, county objectives for noxious weeds are similar to those of the state; counties support the goals and objectives of the Utah Noxious Weeds Act for all landowners, including the federal government. Counties expect federal land managers to control weeds on public lands.
Local weed control entities:
- Carbon County Weed Board
- Emery County Weed and Mosquito Board
- Grand County Weed Department
County-specific weed control assessments from Utah Association of Conservation Districts (UACD) and Natural Resource Conservation (NRCS):
- Carbon County Resource Needs Assessment (2012)
- Emery County Resource Needs Assessment (2012)
- Grand County Resource Needs Assessment (2012)
- San Juan County Resource Needs Assessment (2011)
Regional and state weed management plans:
- Utah Division of Wildlife Resources (UDWR) Invasive Weed Control (2009)
- Utah Strategic Plan for Managing Noxious and Invasive Weeds (2004)
Federal land management agencies:
- US Forest Service
- 1986 Manti-La Sal Resource Management Plan [2]
- US Bureau of Land Management
- 2008 Moab Field Office Resource Management Plan
- 2008 Monticello Field Office Resource Management Plan
- 2008 Price Field Office Resource Management Plan
Prevention
Noxious weeds are easily spread by contaminated agricultural machinery, pack stock, riding stock, livestock feed, hay, straw, soils, sod, nursery stock, and manure. Preventive measures include:
- Certified weed-free feed for all stock animals.
- Certified weed-free mixes, mulch, fill, etc., for restoration/rehabilitation activities.
- Thoroughly cleaning agriculture machinery and equipment (which has come in contact with weeds) before it is transported to other locations.
- Prevent spilling and accidental spreading of materials from vehicles transporting seed, feed, topsoil and fill materials.
- Educate landowners, land users, and visitors about the impacts of noxious weeds.
Treatment
Once established, weeds must be treated to control further spread. Treatments include:
- Chemical control and containment (hand, vehicle, aerial)
- Mechanical treatments (mowing, discing)
- Biological (insects, grazing livestock such as goats and cattle)
- Tamarisk beetle is a good example for the SEUALG region
- Physical (water removal, flooding, burning)
The Noxious Weeds data combined with the Ownership data can be used to identify large infestation areas within the county and the ownership of nearby land.
Cooperative Weed Management Areas (CWMAs): These provide weed control across large lands areas, like watersheds, without specific consideration of land ownership, to more effectively treat weeds. CWMAs are also used to coordinate treatment efforts and pool resources. Weed control is most effective when all land managers and landowners act quickly to address infestations when they first begin.
CWMAs and their partners within the WFRC area include;
- Skyline CWMA (Emery and Carbon County)
- Middle Colorado River Watershed (Grand County)
Weed control and treatment resources:
- The UDWR has compiled an Invasive Weed Control document, which provides specific treatment approaches for seven common noxious weeds.
- Denison Mines published a Weed Management Plan for La Sal Mine Complex (San Juan County, Utah). The plan offers specific and helpful preventative measures, control measures, and Reporting strategies.
- The Utah State University Extension weed control program provides information regarding noxious weeds across Utah.
- The Utah Weed Control Association is a professional organization consisting of weed control specialists in Utah.
- The Natural Resources Conservation Service provides detailed noxious weed information.
- The UDOT Chemical Guide for State Noxious Weeds provides information on the prevention of weeds at construction sites
Weeds create significant economic impacts that must be considered in each county’s resource management plan. Annual economic losses in the United States from weeds is over $20 billion [4]. It is estimated that, without the use of herbicides, revenue losses to the agricultural sector would increase by about 500% [5].
Economic considerations for counties include:
- Direct expenditures. The UDWR allocates $200,000 annually to treat weeds [6].
- Reduce range carrying capacity for livestock and grazing. Dyers woad infestations can spread 14% per year and reduce range carrying capacity by 38% [7]. The BLM has estimated costs in the western United States for weed control and lost production at $100,000,000 per year [8].
- Wildland fire. Contiguous patches of weeds pose significant fire risks, and seeding after wildfire is a necessity to recruit native species rather than weeds.
- Agriculture. Direct control costs, crop and seed contamination, and equipment cleaning costs.
- Wildlife habitat. Phragmites outcompetes native wetland vegetation and chokes out wildlife [9].
- Weed control impacts. Fire is a control method often used to treat phragmites, but smoke is a significant air-quality issue, which must be considered in this region.
- Increased wildfire risk and costs. Many noxious weeds, such as cheatgrass, are very flammable and increase the risk of wildfires. After a fire burns an area infested with noxious weeds, the weeds sprout before native plants and are able to dominate native plant species by quickly taking over water and soil resources [10].
- Recreation impacts. Tamarisk and russian olive grow very thick in riparian areas along rivers making it difficult for river users to access recreation resources. Goathead (puncture vine) causes problems for cyclists and trail users.
Data Name | Data Explanation | Publication Date | Spatial Accuracy | Contact |
---|---|---|---|---|
Land Ownership , | Surface Land Ownership; use Admin field to identify administrative agency | Updated Weekly | 1:24,000 | State of Utah School and Institutional Trust Lands Administration (SITLA). GIS Group |
Noxious Weeds in Utah | Identified weed locations in Utah | 1/18/2013 | Variable | AGRC |
Early Detection Distribution Maps (EDDMaps) | Early detection and distribution mapping system (requires free log in) | Live data | Variable | Center for Invasive Species and Ecosystem Health |
References
- Utah State Legislature. 2015. Utah Noxious Weed Act – Administrative Rules. Enacted July 2, 2008, Modified December 15, 2015. (Accessed January 25, 2016.)
- US Forest Service. 1986. Manti-La Sal National Forest Land and Resource Management Plan.
- Beck, G. K. Economics of Invasive Weed Control: Chemical, Manual/ Physical/Fire, Biological, and Doing Nothing. Invasive Plant Management Technical Webinar Series.
- Utah State University. 2010. Noxious Weed Field Guide 4th Edition.
- Utah Weed Control Association. 2004. The Utah Strategic Plan for Managing Noxious and Invasive Weeds.
- Utah Department of Natural Resources, Utah Division of Wildlife Resources. 2009. Information Document for Invasive and Noxious Weed Control Project on Utah’s Waterfowl Management Areas. Publication No. 09-14., Salt Lake City, Utah.
- US Department of the Interior, Bureau of Land Management, Oregon State Office. 1985. Northwest Area noxious weed control program: Environmental Impact Statement–Final. Portland, OR: US Department of the Interior, Bureau of Land Management, Oregon State Office.
- US Department of the Interior, Bureau of Land Management. 2011. “Noxious Weeds – A Growing Problem Uintah Basin Weed Management Partnership.” Accessed: 2/15/16.
- Schuske, K. 2013. An Invasive Grass Is Choking Utah’s Wetlands. Explore Utah Science. Accessed: 2/15/16.
- Idaho Firewise. 2015. Wildfire and Idaho Landscape. Website accessed: 2/16/16.