Technical Abstract: Shieldcress (Lepidium perfolatum) is an exotic, self invasive annual weed native to Central Asia. It was introduced to the Intermountain Area early in the 20th century. For many years it has been a minor weed species found in the area between the salt desert and Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) vegetation zones. Either the weed has changed and become more competitive or the environment of the degraded communities has changed to allow this spread and dominance. This dominance has decreased forage and utilization as well as changing the wildfire characteristics of these invaded sites.