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awnless wild-rye, awnless wlldrye, beardless wild rye

Canada wild rye, Canadian wild rye, Great Plains wild-rye, élyme du Canada

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

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

nodes 6-9, concealed or exposed, glabrous.

(40)60-150(180) cm, erect or decumbent;

nodes 4-10, mostly concealed by the leaf sheaths, 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 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.

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.

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.

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.

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.

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.

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.

Anthesis

late June to mid-August.

May to July.

2n

= 28, 42.

= 28, rarely 42.

Elymus curvatus

Elymus canadensis

Distribution
from USDA
[WildflowerSearch map]
[BONAP county map]
from FNA
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
[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 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.)

Key
1. Lemmas usually villous or hispid; spikes nodding to almost pendent; internodes 4-7 mm long, often strongly glaucous
var. canadensis
1. Lemmas usually smooth or scabridulous, occasionally hirsute; spikes usually nodding, occasionally almost erect; internodes 3-4 mm long, not strongly glaucous.
→ 2
2. Glumes not clearly indurate or bowed out at the base, awns 10-20 mm long; lemmas smooth or scabridulous, awns usually 20-30 mm long, moderately outcurving; spikes 6-20 cm long
var. brachystachys
2. Glumes often slightly indurate and bowed out at the base, awns 15-25 mm long; lemmas occasionally hirsute, awns 30-40 mm long, often strongly outcurving; spikes 15-25(30) cm long
var. robustus
Source FNA vol. 24, p. 300. FNA vol. 24, p. 303.
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. 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. 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
Subordinate taxa
E. canadensis var. brachystachys, E. canadensis var. canadensis, E. canadensis var. robustus
Synonyms E. virginicus var. submuticus, E. virginicus var. jenkinsii, E. submuticus
Name authority Piper L.
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