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awnless wild-rye, awnless wlldrye, beardless wild rye

early wild-rye

Habit Plants cespitose, not rhizomatous, often glaucous. Plants cespitose, not rhizomatous, usually glaucous.
Culms

60-110 cm, stiffly erect, or the base sometimes geniculate;

nodes 6-9, concealed or exposed, glabrous.

40-120 cm, erect or slightly decumbent;

nodes 4-8, mostly exposed, glabrous.

Leaves

evenly distributed;

sheaths glabrous, often reddish brown;

auricles to 1 mm, sometimes absent;

ligules shorter than 1 mm, ciliolate;

blades 5-15 mm wide, the lower blades usually lax, shorter, narrower, and senescing earlier, the upper blades usually ascending and somewhat involute, adaxial surfaces smooth or scabridulous, occasionally scabrous.

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.

Spikes

9-15 cm long, (0.5)0.7-1.3 cm wide, erect, exserted or the bases slightly sheathed, with 2 spikelets per node;

internodes 2.5-4.5 mm long, about 0.25-5 mm thick at the thinnest sections, smooth or scabrous beneath the spikelets.

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.

Spikelets

10-15 mm, appressed, often reddish brown at maturity, with (2)3-4(5) florets, lowest florets functional;

disarticulation below the glumes and beneath the florets, or the lowest floret falling with the glumes.

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.

Glumes

equal or subequal, the basal 2-3 mm terete, indurate, strongly bowed out, without evident venation, glume bodies 7-15 mm long, 1.2-2.1 mm wide, linear-lanceolate, widening above the base, 3-5-veined, usually glabrous or scabrous, occasionally hispidulous, rarely hirsute on the veins, margins firm, awns 0-3(5) mm;

lemmas 6-10 mm, glabrous or scabrous, rarely hirsute, awns (0.5)1-3(4) mm, rarely 5-10 mm on the lemmas of the distal spikelets, straight;

paleas 6-10 mm, obtuse, often emarginate;

anthers 1.5-3 mm.

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.

Anthesis

late June to mid-August.

usually mid-May to mid-June.

2n

= 28, 42.

= 28.

Elymus curvatus

Elymus macgregorii

Distribution
from USDA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MO; MS; NC; ND; NE; NH; NY; OH; OK; PA; RI; SD; TN; TX; VA; VT; WI; WV; NS; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Elymus curvatus grows in moist or damp soils of open forests, thickets, grasslands, ditches, and disturbed ground, especially on bottomland. It is widespread from British Columbia and Washington, through the Intermountain region and northern Rockies, to the northern Great Plains. It is infrequent or rare in the midwest, the Great Lakes region, and the northeast, and is virtually unknown in the southeast. It is similar to E. virginicus (p. 298), and has sometimes been included in that species as E. virginicus var. submuticus Hook., but is more distinct than the varieties of E. virginicus treated above. Although E. virginicus and E. curvatus overlap greatly in range, E. curvatus usually has a distinct growth form, and its anthesis is 1-2 weeks later (Brooks 1974). Its spikes range from being completely exserted, especially west of the Great Plains, to largely sheathed, especially east of the Mississippi River and in more stressed environments. This geographic trend parallels that within E. virginicus, but sheathed plants of E. curvatus can usually be distinguished by their short awns. Clear transitions to E. virginicus, usually var. jejunus, are rare, but, especially from Missouri to Wisconsin, there are occasional plants with 5-10 mm awns on a few lemmas, especially at the spike tips. Rarely, plants from Missouri and Iowa to Quebec have hispid to hirsute spikelets, suggesting introgression with E. virginicus var. intermedius. There are a few records of apparent hybrids with other species.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

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.)

Source FNA vol. 24, p. 300. FNA vol. 24, p. 295.
Parent taxa Poaceae > subfam. Pooideae > tribe Triticeae > Elymus Poaceae > subfam. Pooideae > tribe Triticeae > Elymus
Sibling taxa
E. alaskanus, E. albicans, E. arizonicus, E. bakeri, E. canadensis, E. caninus, E. churchii, E. ciliaris, E. dahuricus, E. diversiglumis, E. elymoides, E. glabriflorus, E. glaucus, E. hirsutus, E. hoffmannii, E. hystrix, E. interruptus, E. lanceolatus, E. macgregorii, E. macrourus, E. multisetus, E. pringlei, E. repens, E. riparius, E. scribneri, E. semicostatus, E. sibiricus, E. sierrae, E. stebbinsii, E. svensonii, E. texensis, E. trachycaulus, E. tsukushiensis, E. villosus, E. violaceus, E. virginicus, E. wawawaiensis, E. wiegandii, E. ×cayouetteorum, E. ×ebingeri, E. ×hansenii, E. ×palmerensis, E. ×pinalenoensis, E. ×pseudorepens, E. ×saundersii, E. ×yukonensis
E. alaskanus, E. albicans, E. arizonicus, E. bakeri, E. canadensis, E. caninus, E. churchii, E. ciliaris, E. curvatus, E. dahuricus, E. diversiglumis, E. elymoides, E. glabriflorus, E. glaucus, E. hirsutus, E. hoffmannii, E. hystrix, E. interruptus, E. lanceolatus, E. macrourus, E. multisetus, E. pringlei, E. repens, E. riparius, E. scribneri, E. semicostatus, E. sibiricus, E. sierrae, E. stebbinsii, E. svensonii, E. texensis, E. trachycaulus, E. tsukushiensis, E. villosus, E. violaceus, E. virginicus, E. wawawaiensis, E. wiegandii, E. ×cayouetteorum, E. ×ebingeri, E. ×hansenii, E. ×palmerensis, E. ×pinalenoensis, E. ×pseudorepens, E. ×saundersii, E. ×yukonensis
Synonyms E. virginicus var. submuticus, E. virginicus var. jenkinsii, E. submuticus
Name authority Piper R. Brooks & J.J.N. Campb.
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