Bromus tectorum |
Bromus sitchensis |
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cheat brome, cheat grass, downy brome, downy chess, drooping brome |
Alaska brome, Sitka brome |
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Habit | Plants annual. | Plants perennial; loosely cespitose. |
Culms | 5-90 cm, erect, slender, puberulent below the panicle. |
120-180 cm tall, 3-5 mm thick, erect. |
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. |
glabrous or sparsely pilose; auricles absent; ligules 3-4 mm, glabrous or hairy, obtuse, lacerate; blades 20^40 cm long, 2-9 mm wide, flat, sparsely pilose adaxially or on both surfaces. |
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. |
25-35 cm, open; lower branches to 20 cm, 2-4(6) per node, spreading, often drooping, with 1-3 spikelets on the distal 1/2 sometimes confined to the tips. |
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. |
18-38 mm, elliptic to lanceolate, strongly laterally compressed, with (5)6-9 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. |
glabrous, sometimes scabrous; lower glumes 6-10 mm, 3-5-veined; upper glumes 8-11 mm, 5-7-veined; lemmas 12-14(15) mm, lanceolate, laterally compressed, 7-11-veined, strongly keeled at least distally, usually glabrous, sometimes hirtellous, margins sometimes sparsely pilose, apices entire or with acute teeth, teeth shorter than 1 mm; awns 5-10 mm; anthers to 6 mm. |
2n | = 14. |
= 42, 56. |
Bromus tectorum |
Bromus sitchensis |
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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
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AK; CA; OR; WA; BC
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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 sitchensis grows on exposed rock bluffs and cliffs, and in meadows, often in the partial shade of forests along the ocean edge, and on road verges and other disturbed sites. Its range extends from the Aleutian Islands and Alaska panhandle through British Columbia to southern California. Bromus sitchensis resembles B. aleutensis, the two sometimes being treated as conspecific varieties. Bromus sitchensis is predominantly outcrossing, while B. aleutensis is predominantly self-fertilizing (C.L. Hitchcock 1969). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 226. | FNA vol. 24, p. 201. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Genea | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Ceratochloa |
Sibling taxa | ||
Synonyms | B. tectorum var. nudus, B. tectorum var. glabratus, Anisantha tectorum | |
Name authority | L. | Trin. |
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