ARS | Publication request: The effects of downy brome invasion on mule deer habitat

Submitted to: Western Society of Weed Science
Publication Type: Abstract Only
Publication Acceptance Date: October 27, 2011
Publication Date: March 15, 2012
Citation: Clements, C.D., Young, J.A., Harmon, D.N. 2012. The effects of downy brome invasion on mule deer habitat [abstract]. Western Society of Weed Science. 64:14.

Technical Abstract: Downy brome (Bromus tectorum), also widely known as cheatgrass, is a highly invasive exotic weed that has spread over millions of hectares of rangelands throughout the Intermountain West. Native to Eurasia, this early maturing annual provides a fine textured fuel that increases the chance, rate, season and spread of wildfires. Historical wildfire intervals estimated at 60-110 years are now as frequent as every 5-10 years. In 1964 a firestorm, largely fueled by downy brome, swept through Elko County in northeastern Nevada burning 120,000 hectares of rangelands. Most of the burned area was converted from big sagebrush (Artemisia tridentata)/bunchgrass communities to downy brome dominance. In 1999, over 765,000 hectares burned in Nevada, consuming more critical browse communities. Before the firestorm of 1964, the Independence mule deer (Odocoileus hemionus) herd of northeastern Nevada was estimated at 38,000 animals. By 2001, the Independence mule deer herd was estimated at 9,000 animals. The use of herbicide and mechanical treatments combined with the seeding of native and introduced species was aggressively applied on selected areas to provide forage and cover to wintering mule deer. Understanding the importance of the inherent potential of specific seed species to compete with and suppress downy brome resulted in increased success of rehabilitation efforts. By 2010, the Independence mule deer herd was estimated at 14,000, 65% increase. Active and aggressive weed control practices of downy brome along with effective rehabilitation practices are critical in decreasing the frequency and intensity of wildfires as well as any hope at returning native shrubs back to the community for mule deer and other wildlife species.