A Guide to Weeds in British Columbia

CHEATGRASS DISTRIBUTION

Bromus tectorum L. Family: (Grass). Other Scientific Names: None. Other Common Names: Downy brome, downy chess, early chess, drooping brome, downy cheat, slender chess, downy bromegrass, military grass, broncograss, Mormon oats. Legal Status: Not categorized.

Growth form: Annual Stems: Mature are or winter annual grass. generally 10–75 cm tall. Stems Flower: Cheatgrass are erect, slender, glabrous, or panicles change colour from slightly hairy. green to purple to brown as the Roots: The finely divided matures and eventually fibrous root system typically dries. Branches are slender, reaches a depth of about 30 drooping, hairy, flexuous, with cm but can grow to 150 cm up to 8 . deep in the field (Hironaka Seeds/Fruit: Spikelets including 1961; Hulbert 1955). awns are 2–5 cm long, Seedling: Distinguished by nodding, with 2–8 florets. hairy leaf blades and sheaths. Leaves: Leaves are light green Similar Species and hairy. Sheaths are fused except near the node at the Exotics: Similar to Japanese bottom of each sheath. The brome ( japonicus) and lower sheaths are brome (Bromus secalinus). conspicuously hairy, while the Natives: None known. upper sheaths are sometimes smooth.

Impacts ______Agricultural: Cheatgrass can be troublesome in winter The plant competes effectively for moisture with wheat and other crops. Awns many injure livestock and climax dominants such as bluebunch wheatgrass animals’ eyes and mouths, but the plant has good (Elymus spicatus) and can interrupt the rate of spring forage values before seed-set (Stubbendieck et successional change from low stages of succession to al. 1997). higher stages of succession for long periods of time Ecological: Can form dense stands on sites that were (Harris 1967). previously disturbed, especially overgrazed areas. Human: No information available.

Habitat and Ecology ______General requirements: In BC, cheatgrass grows at grasslands (Upadhaya et al. 1986). It can invade low- to mid-elevations at the coast, and in the rangelands that have never been grazed by livestock grasslands and dry forests of the Interior. It is common (Svejcar and Tausch 1991). in recently burned rangeland, winter crops, disturbed Distribution: Cheatgrass is common in southern parts areas, abandoned fields, eroded areas, and overgrazed but rare elsewhere in the province (Douglas et al. 1990) 24 A Guide to Weeds in British Columbia

It is present in all agricultural reporting regions by flowering within a week, and seeds mature in mid- except the Peace River but is not considered a major to late June (Upadhaya et al. 1986). concern in any region. Mode of reproduction: By seed. Historical: Introduced from Eurasia, possibly in ship Seed production: Cheatgrass can produce up to 450 ballast. Found at Spences Bridge as early as 1890 kg seeds/ha, depending on plant density and (Mosley et al. 1999). environmental conditions (Upadhaya et al. 1986). Life cycle: A winter annual that can germinate in Seed bank: Generally a low retention of seeds in the autumn or spring when soil moisture is adequate. soil because of high germination rates. Autumn-germinated plants will establish a root system Dispersal: Seeds are dispersed short distances by that allows the plant to take early advantage of spring wind, but the awns can attach to fur or clothing. moisture. Seeds mature about 2 months later (Upadhaya et al. 1986; Stubbendieck et al. 1997). Hybridization: No information available. Plant heads appear in late April to early May, followed

Management ______Biocontrol: None. Controlled livestock grazing can Agriculture, Food and Fisheries Crop Production help regulate cheatgrass populations, but grazing Guides for specific recommendations. Before applying prescriptions depend on the mixture of plants in the herbicides, read the label for full use and plant community. precautionary instructions. Mechanical: Ponzetti (1997) reported that repeated Cultural/Preventive: Prevent new infestations by mowing every 3 weeks during spring and summer was minimizing disturbance and seed dispersal and as effective at managing seed production, but this maintaining vigorous perennial plant communities. method was labour-intensive and expensive. Hand-pulling can be effective for a small infestation, Fire: Fire has been effective in the US if plants are especially before the plants set seed. On larger burned after they have dried but before the seeds have infestations, hand-pulling may be required for several dropped (Carpenter and Murray 1998). Some seeds years until the seed bank is depleted. Seed disturbed will survive, and if a fire is not repeated within 3–4 areas to perennial grasses to provide competition. years it is likely the population will re-establish. Herbicides: Spring applications of quizalofop, fluazifop-p-butyl, sethoxydim, and glyphosate have successfully controlled cheatgrass on various rangeland Integrated Management Summary sites in the US. Management was usually best when the Integrated management will require a plants were less than 10 cm tall and growing combination of chemical control, cultural vigorously (Wiese et al. 1995). Autumn applications control, seeding perennial grasses, and proper are generally used in cropland situations by farmers livestock management where land is grazed. growing winter wheat or other cool-season crops. Consult the most recent edition of BC Ministry of

References ______Carpenter, A. T., and T. A. Murray. 1998. Element FEIS—Fire Effects Information System. 1996. stewardship abstract for Bromus tectorum. The Nature Prescribed Fire and Fire Effects Research Work Unit, Conservancy, Wildland Weeds Management and Rocky Mountain Research Station (producer), US Research Program. Forest Service. http://www.fs.fed.us/database/feis/ [12 http://tncweeds.ucdavis.edu/esadocs/bromtect.html Mar 98]. Douglas, B. J., A. G. Thomas, and D. A. Derksen. Harris, G. 1967. Some competitive relationships 1990. Downy brome (Bromus tectorum) invasion into between Agropyron spicatum and Bromus tectorum. southwestern Saskatchewan. Canadian Journal of Ecological Monographs 37: 89–111. Plant Science 70: 1143–1151. Hironaka, M. 1961. The relative rate of root development of cheatgrass and medusahead. Journal of Range Management 14: 263–267.

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Hulbert, L. C. 1955. Ecological studies of Bromus Svejcar, T., and R. Tausch. 1991. Anako Island, tectorum and other annual bromegrasses. Ecological Nevada: A relict area dominated by annual invader Monographs 25: 181–213. species. Rangelands 13: 233–236. Melgoza, G., R. S. Nowak, and R. J. Tausch. 1990. Soil Upadhaya, M. K., R. Turkington, and D. McIlvride. water exploration after fire: Competition between 1986. The biology of Canadian weeds. 75. Bromus Bromus tectorum and two native species. Oecologia tectorum L. Canadian Journal of Plant Science 66: 83: 7–13. 689–709. Mosely, J. C. 1996. Prescribed sheep grazing to West, N. E. (ed.). 1983. Western intermountain suppress cheatgrass: A review. Sheep and Goat sagebrush steppe. Temperate Deserts and Semi- Research Journal 12: 74–81. Deserts. Amsterdam, Neth.: Elsevier Scientific Mosely, J. C., S. C. Bunting, and M. E. Monoukian. Publishing Company. 1999. Cheatgrass. In R. L. Sheley and J. K. Petroff, Whitson, T. D., and D. W. Koch. 1998. Control of eds. Biology and Management of Noxious Rangeland downy brome (Bromus tectorum) with herbicides and Weeds. Corvallis: Oregon State University Press. perennial grass competition. Weed Technology 12: Ponzetti, J. M. 1997. Assessment of medusahead and 391–396. cheatgrass control techniques at Lawrence. Memorial Wiese, A. F., C. D. Salisbury, and B. W. Bean. 1995. Grassland Preserve 1996 Annual Report. The Nature Downy brome (Bromus tectorum), jointed goatgrass Conservancy of Oregon. (Aegilops cylindrica), and horseweed (Conyza Rice, K. J., and R. N. Mack. 1991. Ecological genetics canadensis) control in fallow. Weed Technology 9: of Bromus tectorum: Intraspecific variation in 249–254. phenotypic plasticity. Oecologia 88: 84–90. Young, J. A., and R. A. Evans. 1985. Demography of Stubbendieck, J., S. L. Hatch, and C. H. Butterfield. Bromus tectorum in Artemisia communities. In J. 1997. North American Range Plants. Lincoln: White, ed. The Population Structure of Vegetation. University of Nebraska Press. Dordrecht, Neth.: Dr. W. Junk Publishers.

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