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A number of land managers consider rubber rabbitbrush to be undesirable due to its low forage value (Romo and Eddleman 1988). However, in some areas it may actually enhance the growth of desirable plants. Frischknecht (1963) found late summer and fall growth of crested wheatgrass was more lush under rabbitbrush than under sagebrush or in the open. He attributed this result to the ability of rabbitbrush to trap and retain moisture from snow, and differences between rabbitbrush and crested wheatgrass in root morphology and timing of growth. Rubber rabbitbrush does not produce lateral roots, and its peak growth period is relatively late in the growing season. Control Because rubber rabbitbrush re- sprouts from basal buds, mechanical cultivation and fire typically increase stand density. Chemical control is fairly successful with applications of clopyralid, dicamba, 2 -4 -D ester (Whisenhant 1988) and metsulfuron (Enloe et al. 2009) in mid to late spring when plants have obtained approximately 2 to 3 inches of new growth and soil moisture is still readily available. Contact your local agricultural extension specialist or county weed specialist to determine what works best in your area and how to use it safely. Always read label and safety instructions for each control method. Control measures appear in this document only to provide specific information. USDA NRCS does not guarantee or warranty the products and control methods named, and other products may be equally effective. Pests and Potential Problems Some ecotypes of rubber rabbitbrush are infected by stem galls, which are caused by two species of tephritid flies (Aciurina species) (McArthur 1979). There are no reports of negative effects caused by the galls. Environmental Concerns Although rubber rabbitbrush may appear to dominate a plant community soon after disturbance, it is not overly competitive (McArthur 1979) and is eventually replaced with other vegetation as the community matures (Tirmenstein 1999; Ogle et al. 2009). Seeds and Plant Production Rubber rabbitbrush is fast growing, reaching maturity in 2 to 4 years, and has a lifespan of 5 to 20 years (McArthur and Taylor 2004). Plants begin producing seeds when they are 2 or more years old (Deitschman et al. 1974). Seeds can be harvested in fall or early winter by shaking or stripping the heads from the branches. Processing in a hammer mill followed by a screen fanning mill effectively cleans the seeds prior to sowing. There are about 693,000 rubber rabbitbrush seeds per pound (Deitschman et al. 1974). The seed is non - dormant, although stratification speeds germination (Dietshman et al. 1974) and lowers the temperature at which seeds germinate (Meyer et al. 1989). Seed germination is not dependent on light (Belcher 1985). Germination is relatively high (65 percent) and remains high for up to 3 years in storage with moderate temperature and relative humidity conditions (Stevens et al. 1981). McArthur et al. (1987) found drastic differences in germination rate within and among populations of rubber rabbitbrush. When tested at 37.4 degrees Fahrenheit, collections from hot desert environments germinated the fastest, those from montane and high- latitude environments germinated the slowest, and collections from mid - elevation environments had variable germination rates. Rate of germination is a result of genetic and environmental factors, and is timed to maximize the probability of seedling survival in each habitat (Meyer et al. 1989). Container production in a peat -like media with low nutrition results in a well- rooted seedling in a 40- cubic- inch container in 1 growing season, and a 1 to 2 gallon container in two growing seasons. Given ideal plant nutrition and an extended growing season, rabbitbrush can fill a I to 2 gallon container in asingle growing season. Rubber rabbitbrush can withstand heavy and repeated pruning during production. Cultivars, Improved, and Selected Materials (and area of origin) None Contact your local Natural Resources Conservation Service office for more information. Look in the phone book under United States Government. The Natural Resources Conservation Service will be listed under the subheading "Department of Agriculture." References Aldon, E.F and C.P. Pase. 1981. Plant species adaptability on mine spoils in the Southwest: a case study. Research Note RM -398. USDA Forest Service, Rocky Mountain Forest and Range Exper. Sta., Fort Collins, CO. Anderson, L.C. 1966. Cytotaxonomic studies in Chrysothamnus (Astereae, Compositae). Am. J. Bot. 53:204 -212. Belcher, E. [ed.]. 1985. Handbook on seeds of browse - shrubs and forbs. USDA Forest Service Southern Reg. Tech. Publ. R8 -TP8. Bhat, R.B., B.L. Welch, D.J. Weber, E.D. McArthur. 1990. Mid - winter protein, phosphorus, and digestibility of Chrysothamnus nauseosus subspecies. J. of Range Manage. 43:177 -179. Burke Museum of Natural History and Culture. [Online]. Available at http://biology.burke.washington.edu/herbarium/imag ecol lection.php? Genus= Ericameria &Species = nauseo sa (accessed 10 Nov 2009). University of Washington, Seattle, WA.