Bromus arizonicus |
Bromus latiglumis |
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Arizona brome |
broad-glumed brome, brome a larges glumes, early-leaf brome, flanged brome, hairy woodbrome |
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Habit | Plants annual; tufted. | Plants perennial; not rhizomatous. |
Culms | 30-90 cm tall, to 3 mm thick, erect. |
80-150 cm, erect; nodes 9-20, glabrous, usually concealed by the leaf sheaths; internodes usually glabrous, sometimes hairy just below the nodes. |
Sheaths | retrorsely pilose, sometimes mostly glabrous, throats sometimes with hairs; auricles absent; ligules 1-4 mm, usually glabrous, obtuse, erose; blades 8-18 cm long, 3-9 mm wide, flat, sparsely pilose on both surfaces or the abaxial surfaces glabrous. |
overlapping, densely to moderately retrorsely pilose or glabrous over most of their surface, throats and collars densely pilose; auricles 1-2.5 mm on most lower leaves; ligules 0.8-1.4 mm, hirsute, ciliate, truncate, erose; blades 20-30 cm long, 5-15 mm wide, flat, usually glabrous, rarely pilose, with 2 prominent flanges at the collar. |
Panicles | 12-25 cm, somewhat contracted or open; lower branches shorter than 10 cm, 2-3(5) per node, initially erect to ascending, spreading at maturity, with 1-2 spikelets variously distributed. |
10-22 cm, open, nodding; branches spreading to ascending. |
Spikelets | 18-25 mm, elliptic to lanceolate, strongly laterally compressed, with 4-8 florets. |
15-30 mm, elliptic to lanceolate, terete to moderately laterally compressed, with 4-9 florets. |
Glumes | subequal, smooth or scabrous; lower glumes 8-12.5 mm, 3-veined; upper glumes 9.5-14 mm, 7-veined, about as long as the lowest lemma; lemmas 9.5-14 mm, lanceolate, laterally compressed, prominently 7-veined, strongly keeled at least distally, glabrous or pubescent distally or throughout, marginal hairs, if present, longer than those elsewhere, apices entire or with acute teeth shorter than 1 mm; awns 6-13 mm, sometimes slightly geniculate; anthers 0.4-0.5 mm. |
pubescent or glabrous; lower glumes 4-7.5 mm, 1(3)-veined; upper glumes 6-9 mm, 3-veined, sometimes mucronate; lemmas 8-14 mm, elliptic to lanceolate, rounded over the midvein, backs glabrous or pilose to pubescent, margins long-pilose, apices obtuse to acute, entire; awns 3-4.5(7) mm, straight, arising less than 1.5 mm below the lemma apices; anthers 2-3 mm. |
2n | = 84. |
= 14. |
Bromus arizonicus |
Bromus latiglumis |
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Distribution |
AZ; CA; NV; TX
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CT; DC; DE; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MT; NC; ND; NE; NH; NJ; NY; OH; PA; SD; TN; VA; VT; WI; WV; AB; BC; MB; NB; ON; QC; SK
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Discussion | Bromus arizonicus grows in dry, open areas and disturbed ground of the southwest, usually below 2000 m. Its range extends from California and southern Nevada into Arizona, New Mexico, and northern Mexico. Stebbins et al. (1944) demonstrated that, like Bromus carinatus var. carinatus, B. arizonicus obtained three of its genomes from B. catharticus or a close relative, but the remaining three genomes are not homologous with those in B. carinatus, probably being derived from a species in a section other than Ceratochloa. The small anthers of B. arizonicus strongly suggest that most seed is produced by selfing. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Bromus latiglumis grows in shaded or open woods, along stream banks, and on alluvial plains and slopes. Its range is mainly in the north-central and northeastern United States and adjacent Canadian provinces. Specimens with decumbent, weak, sprawling culms, densely hairy sheaths, and heavy panicles can be called Bromus latiglumis i. incanus (Shear) Fernald. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 201. | FNA vol. 24, p. 209. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Ceratochloa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Bromopsis |
Sibling taxa | ||
Synonyms | B. berteroanus var. excelsus | B. purgans var. latiglumis, B. purgans forma incanus, B. latiglumis forma incanus, B. altissimus |
Name authority | (Shear) Stebbins | (Scribn. ex Shear) Hitchc. |
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