Bromus tectorum

Bromus tectorum, known as downy brome, drooping brome, or cheatgrass, is a winter annual grass native to Europe, southwestern Asia, and northern Africa, but has become invasive in many other areas. It now is present in most of Europe, southern Russia, Japan, South Africa, Australia, New Zealand, Iceland, Greenland, North America, and western Central Asia. In the eastern US, B. tectorum is common along roadsides and as a crop weed, but usually does not dominate an ecosystem. It has become a dominant species in the Intermountain West and parts of Canada, and displays especially invasive behavior in the sagebrush steppe ecosystems, where it has been listed as noxious weed. B. tectorum often enters the site in an area that has been disturbed, and then quickly expands into the surrounding area through its rapid growth and prolific seed production. The reduction of native plants and the increased fire frequency caused by B. tectorum prompted the United States Fish and Wildlife Service (USFW......read more on Wikipedia.