Colorado Statewide Forest Resource Assessment

is legally mandated, as well as dalmation toadfl ax, oxeye daisy, leafy spurge,Russian olive and tamarisk (or salt cedar), which are designated for control inareas where they already occur and for prevention and control where they donot yet occur. Noxious weeds have displaced at least 10 percent of Colorado’snative plant species, including the rare orange mountain dandelion and Uteladies’ tresses, which are under constant threat of extirpation from suchaggressive species as leafy spurge and yellow toadfl ax. Each year, severalColorado children are hospitalized due to severe allergic reactions to myrtlespurge sap. The state’s horse owners also lose an undetermined number ofhorses to the debilitating and irreversible brain damage caused by Russianknapweed (Uhing 2009). Tamarisk poses a particular threat to Colorado’sriparian forests and associated aquatic ecosystems because it crowds outnative plant species, changes natural stream morphology important to nativefi sh species, reduces water availability and increases wildland fi re risks.Noxious Weeds Analysis: While prevention is the best approach for noxiousweeds, a number of management techniques can help mitigate or controlinvasive plants. The Colorado Department of Agriculture (CDA), USFS,counties and others administer programs focused on prevention, eradicationand control of noxious weeds and other invasive plants. 34 These programsalso emphasize rehabilitation and restoration to help heal, minimize or reversethe harmful effects from invasive species (USFS 2004). Rehabilitation actionsare particularly important following wildfi re to prevent the establishment ofaggressive noxious weeds.Map 11 – Invasive Species34For more information on the CDA Noxious Weed Management Program, please see http://www.colorado.gov/cs/Satellite/Agriculture-Main/CDAG/1167928159176.36