Downy Brome (Bromus tectorum)
Similar Species - Smooth brome Bromus inermis
Other Names - Downy chess, cheat grass
Family - Grass Poaceae
Life Cycle - Annual
Habitat - conventional tillage, reduced tillage, forage crops, hay fields, rangeland, irrigation, roadsides, waste areas
- Soft, densely-hairy leaves
- Drooping, purple panicles
- Short, slender awns on seeds
Leaf blades and sheaths of downy brome are pale green and covered with soft, dense hairs on both surfaces and margins. Venation is indistinct except for the midrib on the lower surface. Auricles are absent. The ligule is membranous, approximately 3 mm long and torn along the top.
The plant tillers to produce a tufted clump. The erect stems are slender and usually hairy, and the leaf sheaths are closed at the bottom and split at the top. The root system is fibrous, growing to a depth of about 30 cm. In some areas, downy brome is considered to be forage. Smooth brome, the related forage grass, is a perennial with branching rhizomes and smooth leaves with rough margins. The leaf texture and presence of rhizomes can be used to distinguish smooth brome from downy brome.
The panicle has long, drooping branches. It is pale green and becomes tinged with purple as it matures. Spikelets have hairy, uneven-sized outer glumes and are multi-floreted, each floret developing into one seed. The seeds are also softly hairy with a short, slender, rough awn emerging from just below the tip. Immature heads feel soft to the touch. Smooth brome panicles are not awned and hence, are easily distinguished from downy brome.