Bromus tectorum |
Bromus briziformis |
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cheat brome, cheat grass, downy brome, downy chess, drooping brome |
rattlesnake brome, rattlesnake chess, rattlesnake grass |
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Habit | Plants annual. | Plants annual. |
Culms | 5-90 cm, erect, slender, puberulent below the panicle. |
20-62 cm, erect or ascending. |
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. |
densely pilose; ligules 0.5-2 mm, hairy, obtuse, erose; blades 3-13 cm long, 2-4 mm wide, pilose to pubescent 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. |
5-15 cm long, 3-7 cm wide, open, secund, nodding; branches sometimes longer than the spikelets, curved to reflexed. |
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. |
15-27 mm long, 8-12 mm wide, ovate, laterally compressed; florets 7-15, bases concealed at maturity; rachilla internodes concealed at maturity. |
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. |
smooth or scabridulous; lower glumes 5-6 mm, 3-5-veined; upper glumes 6-8 mm, 7-9-veined; lemmas 9-10 mm long, 6-8 mm wide, inflated, obovate or rhombic, coriaceous, smooth or scabridulous, obscurely 9-veined, rounded over the midvein, margins hyaline, 1-1.3 mm wide, abruptly angled, not inrolled at maturity, apices acute to obtuse, bifid, teeth shorter than 1 mm; awns usually absent, sometimes to 1 mm, arising less than 1.5 mm below the lemma apices; anthers 0.7-1 mm. |
Caryopses | equaling or shorter than the paleas, thin, weakly inrolled or flat. |
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2n | = 14. |
= 14. |
Bromus tectorum |
Bromus briziformis |
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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; CO; CT; DE; ID; IL; IN; MA; MD; MI; MT; ND; NE; NJ; NM; NV; NY; OH; OR; PA; SD; UT; VT; WA; WY; BC; ON
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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 briziformis grows in waste places, road verges, and overgrazed areas. It is native to southwest Asia and Europe, and is adventive in the Flora region, occurring from southern British Columbia to as far south as New Mexico, and in scattered locations eastward. The unique shape of its spikelets has led to its use in dried flower arrangements and as a garden ornamental. The common name may refer to the similarity of the spikelets to a rattlesnake's tail. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 226. | FNA vol. 24, p. 228. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Genea | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Bromus |
Sibling taxa | ||
Synonyms | B. tectorum var. nudus, B. tectorum var. glabratus, Anisantha tectorum | B. brizaeformis |
Name authority | L. | Fisch. & C.A. Mey. |
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