Weed of the Week: Downy Brome

Written by:  Garret Montgomery, Jason Bond, and Tom Eubank

Downy Brome
Family:  Poaceae
Scientific name:  Bromus tectorum L.
Synonyms:  Cheat grass, Drooping bromegrass

Photo: Virginia Tech Weed ID Guide

Downy brome is a tufted, erect, winter annual grass that can reach up to 2.5 feet in height with long, thin, twisted leaf blades from 1 to 9 inches in length.  The ligule is a prominent membrane that may be toothed at the top.  Stems are round and leaf blades are covered on both surfaces with dense, soft hairs.  Leaf sheaths are also hairy.  The seedhead is a loose panicle with multiple drooping, awned spikelets.  Downy brome is often confused with cheat (Bromus secalinus) but can be distinguished by the hairs on the leaf blades.

Downy brome is native to southern Europe but can be found throughout most of the United States except the extreme southeast. It is found in pastures, road sides, yards, and cultivated areas.  Downy brome can be problematic in some areas in winter wheat, pastures, and also in alfalfa. It is common in pastures that have been overgrazed to the point that it can germinate and out-compete forage grasses. The weed can be spread by wind because of its long awns, or seeds can attach to grazing animals. Animals may be infected with tetanus after grazing downy brome because the awns cause injury.  Downy brome can also be toxic in some situations because it can be infected with a fungus that causes ergot.  It should be controlled with glyphosate, paraquat, or tillage in fallow areas and should not be allowed to go to seed in areas where it is becoming a problem.

Bryson, C.T. and M.S. DeFelice. 2009. Weeds of the South. Athens, GA: University of Georgia Press. pp. 358.

Virginia Tech Weed Identification Guide.  http://www.ppws.vt.edu/scott/weed_id/brote.htm

Photo: Virginia Tech Weed ID Guide