Bromus diandrus |
Bromus catharticus |
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great brome, ripgut brome, ripgut grass |
rescue brome, rescue grass, rescuegras |
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Habit | Plants annual. | Plants annual, biennial, or perennial; loosely cespitose or tufted. | ||||
Culms | 20-90 cm, erect or decumbent, puberulent below the panicle. |
30-120 cm tall, 2-4 mm thick, erect or decumbent. |
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Sheaths | softly pilose, hairs often retrorse or spreading; auricles absent; ligules 2-3 mm, glabrous, obtuse, lacerate or erose; blades 3.5-27 cm long, 1-9 mm wide, both surfaces pilose. |
usually densely, often retrorsely, hairy, hairs sometimes confined to the throat; auricles absent; ligules 1-4 mm, glabrous or pilose, obtuse, lacerate to erose; blades 4-30 cm long, 3-10 mm wide, flat, glabrous or hairy on both surfaces. |
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Panicles | 13-25 cm long, 2-12 cm wide, erect to spreading; branches 1-7 cm, stiffly erect to ascending or spreading, with 1 or 2 spikelets. |
9-28 cm, usually open, erect or nodding; lower branches shorter than 10 cm, 1-4 per node, spreading or ascending, with up to 5 spikelets variously distributed. |
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Spikelets | 25-70 mm, sides parallel or diverging distally, moderately laterally compressed, with 4-11 florets. |
(17)20-40 mm, shorter than at least some pedicels and branches, elliptic to lanceolate, strongly laterally compressed, not crowded or overlapping, with 4-12 florets. |
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Glumes | smooth or scabrous, margins hyaline; lower glumes 15-25 mm, 1-3-veined; upper glumes 20-35 mm, 3-5-veined; lemmas 20-35 mm, linear-lanceolate, scabrous, 7-veined, rounded over the midvein, margins hyaline, apices bifid, acuminate, teeth 3-5 mm; awns 30-65 mm, straight, arising 1.5 mm or more below the lemma apices; anthers 0.5-1 mm. |
smooth or scabrous, glabrous or pubescent; lower glumes 7-12 mm, 5-7(9)-veined; upper glumes 9-17 mm, 7-9(11)-veined, shorter than the lowest lemma; lemmas 11-20 mm, lanceolate, laterally compressed, strongly keeled, usually glabrous, sometimes pubescent distally, smooth or scabrous, 9-13-veined, veins often raised and riblike, margins sometimes conspicuous, hyaline, whitish or partly purplish, apices entire or toothed, teeth acute, shorter than 1 mm; awns absent or to 10 mm; anthers 0.5-1 mm in cleistogamous florets, 2-5 mm in chasmogamous florets. |
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2n | = 42, 56. |
= 42. |
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Bromus diandrus |
Bromus catharticus |
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Distribution |
AR; AZ; CA; CO; DC; DE; GA; ID; IL; LA; MA; MD; MO; MT; NC; NJ; NM; NV; NY; OK; OR; SC; TX; UT; VA; WA; HI; BC
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AL; AR; AZ; CA; CO; DC; FL; GA; IA; IL; KS; KY; LA; MD; MO; MS; NC; ND; NE; NJ; NM; NV; NY; OH; OK; OR; PA; SC; SD; TN; TX; UT; VA; HI; AB; NF; ON
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Discussion | Bromus diandrus is native to southern and western Europe. It is now established in North America, where it grows in disturbed ground, waste places, fields, sand dunes, and limestone areas. It occurs from southwestern British Columbia to Baja California, Mexico, and eastward to Montana, Colorado, Texas, and scattered locations in the eastern United States. The common name 'ripgut grass' indicates the effect it has on animals if they consume the sharp, long-awned florets of this species. Bromus diandrus, as treated here, includes B. rigidus Roth. Sales (1993) reduced these two taxa to varietal rank, pointing out that the differences between them in panicle morphology and callus and scar shape are subtle enough that identification of many specimens beyond B. diandrus sensu lato is often impossible. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 224. | FNA vol. 24, p. 199. | ||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Genea | Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Ceratochloa | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | B. rigidus var. gussonei, B. rigidus, Anisantha diandra | Ceratochloa unioloides, B. willdenowii, B. unioloides | ||||
Name authority | Roth | Vahl | ||||
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