Skip to main content
U.S. flag

An official website of the United States government

Invasion by exotic annual grasses and the excessive wildfires they promote are increasing threats to the sagebrush steppe ecosystem of the western United States. Livestock grazing may amplify the problem, since cattle trample soil biocrusts and feed on the native perennial plants that help ecosystems resist cheatgrass invasion.

A team of USGS researchers evaluated changes in plant communities over a 14-year period after livestock grazing was terminated in Browns Park National Wildlife Refuge in Colorado. After livestock were excluded, cheatgrass expanded faster than desirable perennial bunchgrasses or biocrusts, and reached levels that could lead to cheatgrass dominated grasslands. Increases in cheatgrass were highest in areas with more cheatgrass cover prior to grazing exclusion, and lowest in areas with higher initial biocrust and perennial plant cover. These results suggest that resistance to invasion could be improved through restoration, for example, using herbicides to reduce cheatgrass or seeding native perennials in areas impacted by cheatgrass.  

Germino, M.J., Kluender, C.R., and Anthony, C.R., 2022, Plant community trajectories following livestock exclusion for conservation vary and hinge on initial invasion and soil-biocrust conditions in shrub steppe: Conservation Science and Practice, e12838, Online.

Get Our News

These items are in the RSS feed format (Really Simple Syndication) based on categories such as topics, locations, and more. You can install and RSS reader browser extension, software, or use a third-party service to receive immediate news updates depending on the feed that you have added. If you click the feed links below, they may look strange because they are simply XML code. An RSS reader can easily read this code and push out a notification to you when something new is posted to our site.