Elymus lanceolatus
Elymus diversiglumis
streambank wheatgrass, streamside wild rye, thick-spike wildrye, thickspike wheatgrass
diverseglume wildrye, unequal-glumed wildrye
22-130 cm, erect;
nodes glabrous.
70-160 cm, erect;
nodes 4-9, mostly exposed, glabrous.
often mostly basal, sometimes more evenly distributed;
sheaths glabrous or pubescent;
auricles usually present on the lower leaves, 0.5-1.5 mm;
ligules 0.1-0.5 mm, erose, sometimes ciliolate;
blades 1.5-6 mm wide, generally involute, abaxial surfaces usually glabrous, adaxial surfaces strigose, ribs subequal in size and spacing.
evenly distributed;
sheaths glabrous, often purplish;
auricles 1-2 mm, purplish or brownish black;
ligules usually 1-2 mm;
blades 5-17 mm wide, lax, adaxial surfaces usually pilose, at least on the veins, occasionally scabrous.
3.5-26 cm long, 0.5-1 cm wide, erect to slightly nodding, usually with 1 spikelet per node, sometimes with 2 at a few nodes;
internodes 3.5-15 mm long, 0.1-0.8 mm wide, glabrous or hairy.
8-28 cm long, 3-5 cm wide, nodding to pendent, with 2 spikelets per node, rarely with 1 or 3 at a few nodes;
internodes 4-6(9) mm long, 0.2-0.3 mm thick at the thinnest sections, margins and summits often pubescent.
8-31 mm, 1.5-3 times longer than the internodes, appressed, with 3-11 florets;
rachillas glabrous or hairy, hairs to 1 mm;
disarticulation above the glumes, beneath each floret.
10-16 mm, appressed, with 2-4(5) florets, lowest florets functional;
disarticulation above the glumes, beneath each floret.
subequal, 5-14 mm long, 1/2 - 3/4 the length of the adjacent lemmas, 0.7-1.3 mm wide, lanceolate, glabrous or hairy, smooth or scabrous, 3-5-veined, flat or weakly, often asymmetrically keeled, keels straight, margins narrow, tapering from the base or from beyond midlength, apices acute to acuminate, sometimes mucronate or shortly awned;
lemmas 7-12 mm, glabrous or hairy, hairs all alike, sometimes scabrous, acute to awn-tipped, awns to 2 mm, straight;
paleas about equal to the lemmas, keels straight below the apices, smooth or scabrous proximally, sometimes hairy, scabrous distally, intercostal region glabrous or with hairs, apices 0.2-0.3 mm wide;
anthers (2.5)3-6 mm.
usually differing in length by at least (3)4 mm, occasionally obsolete, (1)2-15(20) mm long including the undifferentiated awns, indurate at the base, (0.1)0.2-0.4(0.6) mm wide, setaceous, 0-1-veined, tapering from the base, scabrous or hispidulous at least towards the apices, margins firm, awns often outcurving;
lemmas 7-12 mm, usually silvery-hirsute to sericeous, occasionally hirtellous or strigose, at least near the margins, backs sometimes scabrous, awns 18-35 mm, moderately to strongly outcurving at maturity;
paleas 7-10 mm, obtuse, occasionally emarginate;
anthers 2-4 mm.
from early June to late July.
= 28.
= 28.
Elymus lanceolatus
Elymus diversiglumis
Elymus lanceolatus grows in sand and clay soils and dry to mesic habitats. It is found primarily in the western half of the Flora region, between the coastal mountains and 95° W longitude, with the exception of E. lanceolatus subsp. psammophilus, which extends around the Great Lakes. Three subspecies are recognized, primarily on the basis of their lemma and palea pubescence.
Elymus lanceolatus is primarily outcrossing, and hybridizes with several species of Triticeae. Elymus albicans (p. 334) is thought to be derived from hybridization with the awned phase of Pseudoroegneria spicata (p. 281). Judging from specimens of controlled hybrids, hybridization with E. trachycaulus (p. 321) and unawned plants of P. spicata probably occur, but would be almost impossible to detect without careful observation in the field. Experimental hybrids are partially fertile, and capable of backcrossing to either parent (Dewey 1965, 1967, 1968, 1975, 1976).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Elymus diversiglumis grows in moist to dry, often base-rich and alluvial soils, in open woods, woodland margins, and thickets in the northern Great Plains, from Saskatchewan and Manitoba to Wyoming, Wisconsin, and Iowa.
Elymus diversiglumis is a variable species that, like E. svensonii (p. 314) and E. churchii (p. 314), may have originated from hybrids between E. canadensis var. canadensis (p. 305) and E. hystrix (see next), although part of its range extends further west than the current distribution of the latter species. Elymus diversiglumis usually reaches anthesis 2-4 weeks earlier than sympatric populations of E. canadensis. Church (1954, 1958, 1967a) found that most artificial canadensis-hystrix hybrids, as well as some plants of E. diversiglumis itself, are sterile. Those that were not sterile could occasionally form fertile backcrosses with E. canadensis and, to a lesser extent, with E. hystrix. Introgressant populations involving all three species are known. Artificial crosses with other species have not been successful.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Lemmas densely hairy, hairs flexible, some 1 mm long or longer | subsp. psammophilus |
1. Lemmas glabrous or with stiff hairs shorter than 1 mm. | → 2 |
2. Lemmas with hairs, not scabrous | subsp. lanceolatus |
2. Lemmas smooth, sometimes scabrous distally, mosdy glabrous, sometimes the lemma margins hairy proximally | subsp. riparius |
BC
OR
WA
CalFlora
Flora NW
IL Wildflowers
MI Flora
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
MN Wildflowers
MO Plants
