Elymus macgregorii
Elymus ×ebingeri
early wild-rye
wildrye
40-120 cm, erect or slightly decumbent;
nodes 4-8, mostly exposed, glabrous.
50-135 cm, usually smooth, glabrous, sometimes retrorsely hairy;
nodes glabrous or hairy.
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 smooth or scabridulous, hairy;
ligules to 1 mm;
blades 14-26 cm long, to 12 mm wide, flat, both surfaces scabridulous, adaxial surfaces hairy.
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.
8-17 cm, with (1)2+ spikelets per node;
internodes 4-8 mm.
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.
diverging at about 45° from the rachises, not patent.
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.
usually subequal, 15-20 mm, bases indurate, bodies lanceolate to subulate, scabrous, sometimes the lower glumes reduced to a stub;
lemmas 8-10 mm, glabrous or strigose, sometimes scabrous, awns 23-29 mm, straight, scabrous;
anthers 2-2.9 mm.
seldom formed.
usually mid-May to mid-June.
= 28.
Elymus macgregorii
Elymus ×ebingeri
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 ×ebingeri is the name for hybrids between E. virginicus (p. 298) and E. hystrix (p. 316). It is frequently found where the two parental species grow together, often with later hybrid generations and introgressants to the two parents. It has been reported from southern Ontario, and from Wisconsin to New York and Illinois. Most published reports simply refer to the existence of these hybrids, the name itself not having been published until 1996.
Elymus ×ebingeri is an Elymus named hybrid
Elymus is notorious for its ability to hybridize. Most of its interspecific hybrids are partially fertile, permitting introgression between the parents. The descriptions provided below are restricted to the named interspecific hybrids. They should be treated with caution and some skepticism; some are based solely on the type specimen, because little other reliably identified material was available. Moreover, as the descriptions of the non-hybrid species indicate, many other interspecific hybrids exist.
The parentage of all hybrids is best determined in the field. Perennial hybrids, such as those in Elymus, can persist in an area after one or both parents have died out, but the simplest assumption is that both are present. Interspecific hybrids of Elymus that have disarticulating rachises presumably have E. elymoides or E. multisetus as one of their parents.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Go Botany
IL Wildflowers
KS Wildflowers
LA Plants
MD Biodiversity
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
