Elymus glabriflorus |
Elymus canadensis |
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southeastern wild-rye |
Canada wild rye, Canadian wild rye, Great Plains wild-rye, élyme du Canada |
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Habit | Plants cespitose, not rhizomatous, often glaucous. | Plants loosely cespitose, rarely with rhizomes to 4 cm long and 1-2 mm thick, often glaucous. | ||||||||
Culms | 60-140 cm, erect; nodes 6-9, mostly concealed, glabrous. |
(40)60-150(180) cm, erect or decumbent; nodes 4-10, mostly concealed by the leaf sheaths, glabrous. |
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Leaves | evenly distributed; sheaths glabrous or pubescent, often reddish brown; auricles absent or to 2 mm, usually purplish brown; ligules shorter than 1 mm; blades 7-15 mm wide, lax or somewhat involute and ascending, usually dull green, sometimes with a glaucous bloom, adaxial surfaces glabrous or densely short-villous. |
evenly distributed; sheaths smooth or scabridulous, glabrous or hirsute, often reddish brown; auricles 1.5-4 mm, brown or purplish black; ligules to 1(2) mm, truncate, ciliolate; blades (3)4-15(20) mm wide, usually firm, often ascending and somewhat involute, usually dull green, drying to grayish, adaxial surfaces usually smooth or scabridulous and glabrous, rarely sparsely hispid to villous. |
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Spikes | 6-20 cm long, (2) 2.5-4(5.5) cm wide, erect, exserted, with (10)18-30(36) nodes, usually with 2(3) spikelets per node, occasionally with up to 5 at some nodes; internodes 3-5 mm long, 0.3-0.8 mm thick and usually 4-angled at the thinnest sections, glabrous or pubescent beneath the spikelets. |
6-30 cm long, 3-7 cm wide, usually nodding, sometimes pendent or almost erect, usually with 2(3) spikelets per node, occasionally to 5 at some nodes, rarely with 1 at some nodes but never throughout; internodes (2)3-5(7) mm long, or 5-10 mm long towards the base, 0.2-0.35 mm thick at the thinnest sections, glabrous or with a few hairs below the spikelets. |
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Spikelets | 10-20 mm, strongly divergent, often reddish brown at maturity, with (2)3-5(6) florets, lowest florets functional; disarticulation below the glumes and each floret, or the lowest floret often falling with the glumes. |
12-20 mm excluding the awns, more or less divergent, with (2)3-5(7) florets, lowest florets functional; disarticulation usually above the glumes and beneath each floret, rarely also below the glumes. |
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Glumes | equal or subequal, entire, the basal 1-3 mm terete, indurate, moderately bowed out, without evident venation, glume bodies 7-18 mm long, (0.7)0.9-1.7 mm wide, linear-lanceolate, widening above the base, (3)4-5(7)-veined, smooth or scabrous, sometimes hirsute, margins firm, awns (10)15-25(30) mm, straight except the awns of the lowest spikelets frequently contorted; lemmas 6-13 mm, smooth, scabrous, or hirsute, awns (15)25-35(40) mm, straight except the awns of the lowest spikelets occasionally contorted; paleas 6-12 mm, obtuse; anthers 2-4 mm. |
usually equal, occasionally subequal, 11-40 mm including the awns, the basal 0-1 mm subterete and slightly indurate, glume bodies 6-13 mm long, 0.5-1.6 mm wide, linear-lanceolate to subsetaceous, entire, widening or parallel-sided above the base, 3-5-veined, glabrous to scabrous-ciliate, rarely villous on the veins, margins firm, awns (5)10-25(27) mm, straight to outcurving; lemmas 8-15 mm, glabrous, scabrous, hispid, or uniformly villous with the hairs generally appressed, awns (10)15-40(50) mm, moderately to strongly outcurving, often contorted at the spike bases; paleas 7-13 mm, acute, usually bidentate; anthers 2-3.5 mm. |
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Anthesis | usually mid-June to late July. |
May to July. |
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2n | = 28. |
= 28, rarely 42. |
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Elymus glabriflorus |
Elymus canadensis |
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Distribution |
AL; AR; CT; DC; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MO; MS; NC; NH; NJ; OH; OK; SC; TN; TX; VA; VT; WV
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AR; AZ; CA; CO; CT; DC; DE; IA; ID; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; 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; AB; BC; MB; NB; NT; ON; QC; SK
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Discussion | Elymus glabriflorus grows on moist, damp, or dry soil in open woods, thickets, and tall grasslands, sometimes spreading into old fields and roadsides. It is found in most of the southeastern United States, extending north to Iowa, Illinois, Indiana, West Virginia, and along the Atlantic coast to Maine; it is rare north of Maryland. Anthesis is usually 2-4 weeks later than in E. virginicus (see next) and other sympatric taxa, even in Texas, where it occurs up to a month earlier than the dates given (Davies 1980). Elymus glabriflorus varies greatly in its pubescence, but without clear taxonomic relevance. Plants that combine pubescent spikelets and, usually, pubescent leaves with somewhat shorter spikes (6-12 cm versus 9-20 cm) and lemmas (6-10 mm versus 7-13 mm) are typical on relatively dry, infertile soils, especially in hilly interior regions, and are less frequent on the southeastern coastal plain. They have been named E. glabriflorus var. australis (Scribn. & C.R. Ball) J.J.N. Campb. In contrast, glabrous to scabrous plants that are often more robust usually grow on relatively moist or damp soils of bottomlands and upland depressions. Elymus glabriflorus is most closely related to E. macgregorii (see previous) and E. virginicus, forming occasional hybrids with both (Campbell 2000). It is sometimes confused with E. villosus (p. 302), from which it differs in having erect spikes, and glumes that are bowed out and disarticulate at maturity. It has also been confused with E. canadensis, especially E. canadensis var. robustus (p. 305), which may be derived from introgressants between the two species (Davies 1980). Hybrids with E. hystrix (p. 316) are also known, with apparent introgression at some range margins. Artificial crosses with other species failed in several cases (Church 1967a, 1967b). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Elymus canadensis grows on dry to moist or damp, often sandy or gravelly soil on prairies, dunes, stream banks, ditches, roadsides, and disturbed ground, or, especially to the south, in thickets and open woods near streams. It is widespread in most of temperate North America, extending from the southwestern Northwest Territories to Coahuila, Mexico, being especially common in the Great Plains. Reports from California and the southeastern states appear to be based on misidentifications. E. canadensis is considered a good forage species. Elymus canadensis is sometimes confused with E. riparius (see previous), from which it differs in having curved rather than straight awns; and with E. wiegandii (p. 305), from which it differs in its less robust habit and narrower leaves. It can hybridize with E. glabriflorus (p. 296), E. virginicus (p. 298), E. hystrix (p. 316) and allies, E. glaucus (p. 306), E. trachycaulus (p. 321), Pseudoroegneria spicata (p. 281), and other species. Subsequent introgression may have contributed to much of the diversity within the genus (Pohl 1959; Brown and Pratt 1960; Nelson and Tyrl 1978; Davies 1980; Campbell 2002). The three varieties recognized here show clear differences in their typical expression and evidence some geographic separation, but they may prove to be artificial reference points within a more or less continuous variation (Sanders et al. 1979). Nevertheless, crossing barriers sometimes exist between the varieties, and even between some sympatric strains (Church 1954, 1958, 1967a). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 296. | FNA vol. 24, p. 303. | ||||||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | ||||||||
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Synonyms | E. virginicus var. glabriflorus, E. virginicus var. australis, E. virginicus forma australis, E. glabriflorus var. australis, E. australis | |||||||||
Name authority | (Vasey ex L.H. Dewey) Scribn. & C.R. Ball | L. | ||||||||
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