Elymus virginicus |
Elymus scribneri |
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common eastern wild-rye, Virginia wild rye, élyme de virginie |
Scribner's wheat grass, Scribner's wild rye, spreading wheatgrass |
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Habit | Plants cespitose, not rhizomatous, sometimes glaucous, especially in the spikes. | Plants cespitose, not rhizomatous. | ||||||||||||
Culms | 30-130 cm, erect to slightly decumbent; nodes 4-9, concealed or exposed, usually glabrous, rarely pubescent. |
15-35(55) cm, prostrate to strongly decumbent, at least at the base; nodes glabrous. |
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Sheaths | glabrous or shortly pilose; auricles usually present, 0.5-1 mm; ligules 0.2-0.4(0.7) mm, usually truncate, occasionally acute, entire to erose; blades 1.5-4 mm wide, usually involute, adaxial surfaces prominently ribbed. |
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Leaves | evenly distributed; sheaths usually glabrous, rarely hirsute, occasionally reddish or purplish; auricles absent or to 1.8 mm, pale brown; ligules shorter than 1 mm; blades 2-14(18) mm wide, usually spreading or lax, sometimes becoming involute, basal blades similar to the upper blades, adaxial surfaces usually smooth, sometimes scabridulous, usually glabrous, occasionally pubescent. |
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Spikes | (3)4-16(22) cm long, 1-2.2(2.5) cm wide, erect, the bases often sheathed, with 2 spikelets per node, rarely with 3 at some nodes; internodes 3-5 mm long, 0.25-0.5 thick at the thinnest sections, smooth and glabrous, or scabrous, or with hairs beneath the spikelets. |
3.5-10 cm long, 0.8-1.2 cm wide excluding the awns, 3-6 cm wide including the awns, usually with 1 spikelet per node, occasionally with 2 spikelets at the lower nodes; internodes 2.5-5(7) mm long, 0.5-1 mm wide, glabrous, mostly smooth, edges scabrous. |
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Spikelets | 10-15 mm, appressed to slightly divergent, with (2)3-4(6) florets, lowest florets functional; disarticulation below the glumes and each floret, or the lowest floret falling with the glumes. |
9-15 mm long, 6-12 mm wide, appressed to ascending, with 3-6 florets; rachilla internodes 0.8-1.3 mm, scabridulous; disarticulation initially at the rachis nodes, subsequently beneath each floret. |
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Glumes | subequal or equal, the basal 1-4 mm terete, indurate, without evident venation, bowed out, yellowish, glume bodies 7-15 mm long, (0.5)0.7-2.3 mm wide, linear-lanceolate, widening above the base, 3-5(8)-veined, usually smooth or scabridulous, margins firm, awns 3-10(15) mm, straight; lemmas 6-10 mm, scabridulous, glabrous or villous-hirsute, awns (5)8-20(25) mm, straight; paleas 5-9 mm, obtuse; anthers 2-3.5(4) mm. |
4-9 mm long, 0.5-1 mm wide, mostly glabrous, midveins scabrous, 3-5-veined, entire, tapering into a divergent, 12-30 mm awn; lemmas 7-10 mm, usually glabrous, occasionally scabridulous, awned, awns 15-30 mm, divergent, scabridulous; paleas usually longer than the lemmas, apices ciliate, truncate or the veins extending into teeth, teeth about 0.5 mm; anthers 1-1.6 mm. |
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Anthesis | usually mid-June to late July (mid-August). |
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2n | = 28. |
= 28. |
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Elymus virginicus |
Elymus scribneri |
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Distribution |
AL; AR; AZ; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; ND; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; AB; BC; LB; MB; NB; NS; ON; PE; QC; SK
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AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB
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Discussion | Elymus virginicus is widespread in temperate North America, growing as far west as British Columbia and Arizona. It is infrequent to rare in the Rocky Mountains, western Great Plains, and southeastern coastal plain. It is a complex species, divided here into four intergrading varieties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Elymus scribneri grows in rocky areas in open subalpine and alpine regions, at 2500-3200 m, often in windswept locations, in southwestern Alberta and the western United States. It is often confused with E. elymoides (p. 318), but differs from that species in having only one spikelet per node, wider glumes, and more tardily disarticulating rachises. It also resembles E. sierrae (see next), from which it differs in its disarticulating rachises, denser spikes, and shorter anthers. Dewey (1963) concluded that Elymus trachycaulus subsp. andinus consists of hybrids between E. scribneri and E. trachycaulus (p. 321). In addition, several taxonomists have suggested that E. scribneri consists of fertile hybrids between E. violaceus (p. 324) and E. elymoides. This suggestion is supported by the frequency with which the three taxa are sympatric, the morphological variation exhibited by E. scribneri, and cytogenetic data (Dewey 1967). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 298. | FNA vol. 24, p. 330. | ||||||||||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | ||||||||||||
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Synonyms | Agropyron scribneri | |||||||||||||
Name authority | L. | (Vasey) M. E. Jones | ||||||||||||
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