Elymus macgregorii
Elymus virginicus
early wild-rye
common eastern wild-rye, Virginia wild rye, élyme de virginie
40-120 cm, erect or slightly decumbent;
nodes 4-8, mostly exposed, glabrous.
30-130 cm, erect to slightly decumbent;
nodes 4-9, concealed or exposed, usually glabrous, rarely pubescent.
evenly distributed;
sheaths usually glabrous, rarely villous;
auricles 2-3 mm, usually purplish black when fresh, sometimes light brown;
ligules shorter than 1 mm;
blades 7-15 mm wide, lax, dark glossy green under the glaucous bloom, adaxial surfaces usually glabrous, occasionally villous.
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.
4-12 cm long, (1.7)2.2-3(4)4 cm wide, erect, exserted, with (6)9-16(20) nodes and 2 spikelets at all or most nodes, sometimes with 3 at some nodes;
internodes 4-7 mm long, about 0.3 mm thick and 2-angled at the thinnest sections, usually glabrous or scabridulous beneath the spikelets.
(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.
10-15 mm, strongly divergent, glaucous, maturing to pale yellowish brown, with (2)3-4 florets, lowest florets functional;
disarticulation below the glumes and each floret, the lowest floret often falling with the glumes.
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.
subequal, entire, the basal 1-3 mm terete or subterete, indurate, without evident venation, moderately bowed out, glume bodies 8-16 mm long, 1-1.8 mm wide, linear-lanceolate, widening or parallel-sided above the base, (2)4-5(8)-veined, usually glabrous, occasionally hirsute, sometimes scabrous, margins firm, awns (10)15-20(25) mm, straight except the awns of the lowest spikelets occasionally contorted;
lemmas 6-12 mm, usually glabrous, sometimes scabrous, occasionally villous, awns (15)20-30 mm, straight;
paleas 6-10 mm, apices obtuse;
anthers 2-4 mm.
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.
usually mid-May to mid-June.
usually mid-June to late July (mid-August).
= 28.
= 28.
Elymus macgregorii
Elymus virginicus
Elymus macgregorii grows in moist, deep, alluvial or residual, calcareous or other base-rich soils in woods and thickets, mostly east of the 100th Meridian in the contiguous United States. It used to be confused with E. glabriflorus (p. 296) or E. virginicus (p. 298), but it reaches anthesis about a month earlier than sympatric populations of these species. In most of its range, E. macgregorii has purplish black auricles; light brown auricles may be locally abundant, particularly in populations at the limits of its range.
Elymus macregorii hybridizes with several species, but especially E. virginicus and E. hystrix (p. 316) (Campbell 2000). Western plants often have smaller, more condensed spikes and distinctly villous leaves, suggesting a transition to E. virginicus var. jejunus (p. 300). Transitions to E. virginicus var. jejunus can also be recognized to the north, where the dates of anthesis are delayed, but even in Maine, E. macgregorii reaches anthesis about 10 days earlier than E. virginicus (Campbell and Haines 2002). Plants with villous lemmas grow at scattered locations; they have not been reported in distinct habitats, nor in large enough populations to warrant taxonomic recognition.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.)
1. Spikelets hispidulous to villous-hirsute, usually glaucous; anthesis usually in early July to mid-August | var. intermedius |
1. Spikelets usually glabrous or scabrous, glaucous or not; anthesis usually in mid-June to late July. | → 2 |
2. Spikes partly sheathed; glumes 1-2.3 mm wide, strongly indurate and bowed out in the basal 2-4 mm; plants not glaucous, becoming yellowish brown or occasionally somewhat purplish at maturity | var. virginicus |
2. Spikes exserted; glumes (0.5)0.7-1.5(1.8) mm wide, moderately indurate and bowed out in the basal 1-2 mm; plants usually glaucous, becoming yellowish or reddish brown at maturity. | → 3 |
3. Culms usually 70-100 cm tall, with 6-8 nodes; blades 3-15 mm wide, flat; spikes 4-20 cm long, not strongly glaucous; glumes indurate only in the basal 1 mm | var. jejunus |
3. Culms usually 30-80 cm tall, with 4-6 nodes; blades 2-9 mm wide, often becoming involute; spikes 3.5-11 cm long, often strongly glaucous; glumes usually indurate in the basal 1-2 mm | balophilus |
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