Bromus tectorum |
Bromus frondosus |
|
---|---|---|
cheat brome, cheat grass, downy brome, downy chess, drooping brome |
weeping brome |
|
Habit | Plants annual. | Plants perennial; not rhizomatous. |
Culms | 5-90 cm, erect, slender, puberulent below the panicle. |
50-100 cm, erect to spreading; nodes 3-5, usually glabrous, rarely pubescent; internodes glabrous. |
Sheaths | usually densely and softly retrorsely pubescent to pilose, upper sheaths sometimes glabrous; auricles absent; ligules 2-3 mm, glabrous, obtuse, lacerate; blades to 16 cm long, 1-6 mm wide, both surfaces softly hairy. |
usually glabrous, sometimes pubescent or pilose, especially the lower sheaths, midrib of the culm leaves usually narrowed just below the collar; auricles absent; ligules 1-3 mm, glabrous, truncate to obtuse, laciniate; blades 10-20 cm long, 3-6 mm wide, flat, often glaucous, usually glabrous, sometimes scabrous, basal blades often pubescent. |
Panicles | 5-20 cm long, 3-8 cm wide, open, lax, drooping distally, usually 1-sided; branches 1-4 cm, drooping, usually 1-sided and longer than the spikelets, usually at least 1 branch with 4-8 spikelets. |
10-20 cm, open; branches ascending and spreading or declining and drooping. |
Spikelets | 10-20 mm, usually shorter than the panicle branches, sides parallel or diverging distally, moderately laterally compressed, often purplish-tinged, not densely crowded, with 4-8 florets. |
15-30 mm, elliptic to lanceolate, terete to moderately laterally compressed, with (4)5-10 florets. |
Glumes | villous, pubescent, or glabrous, margins hyaline; lower glumes 4-9 mm, 1-veined; upper glumes 7-13 mm, 3-5-veined; lemmas 9-12 mm, lanceolate, glabrous or pubescent to pilose, 5-7-veined, rounded over the midvein, margins hyaline, often with some hairs longer than those on the backs, apices acuminate, hyaline, bifid, teeth 0.8-2(3) mm; awns 10-18 mm, straight, arising 1.5 mm or more below the lemma apices; anthers 0.5-1 mm. |
usually glabrous, rarely slightly pubescent, 3-veined; lower glumes 5.5-8 mm; upper glumes 6.5-9 mm, often mucronate; lemmas 8-12 mm, elliptic to lanceolate, rounded over the midvein, backs pubescent or glabrous, margins usually with longer hairs, apices subulate to obtuse, entire; awns 1.5-4 mm, straight, arising less than 1.5 mm below the lemma apices; anthers 1.5-3.5 mm. |
2n | = 14. |
= 14. |
Bromus tectorum |
Bromus frondosus |
|
Distribution |
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; HI; AB; BC; MB; NB; NS; NT; ON; QC; SK; YT; Greenland
|
AZ; CO; NM; UT
|
Discussion | Bromus tectorum is a European species that is well established in the Flora region and other parts of the world. It grows in disturbed sites, such as overgrazed rangelands, fields, sand dunes, road verges, and waste places. In the southwestern United States, Bromus tectorum is considered a good source of spring feed for cattle, at least until the awns mature. It is highly competitive and dominates rapidly after fire, especially in sagebrush areas. The resulting dense, fine fuels permanently shorten the fire-return interval, further hindering reestablishment of native species. It now dominates large areas of the sagebrush ecosystem of the western Flora region. Specimens with glabrous spikelets have been called Bromus tectorum f. nudus (Klett & Richt.) H. St. John. They occur throughout the range of the species, and are not known to have any other distinguishing characteristics. For this reason, they are not given formal recognition in this treatment. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Bromus frondosus grows in open woods and on rocky slopes, at 1500-2500 m. Its range extends from Colorado, Arizona, and New Mexico into Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 226. | FNA vol. 24, p. 213. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Genea | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Bromopsis |
Sibling taxa | ||
Synonyms | B. tectorum var. nudus, B. tectorum var. glabratus, Anisantha tectorum | |
Name authority | L. | (Shear) Wooton & Standi. |
Web links |
|