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streambank wheatgrass, streamside wild rye, thick-spike wildrye, thickspike wheatgrass

bottlebrush, bottlebrush squirreltail, long-bristle wildrye, squirrel tail grass, squirreltail, western bottle-brush grass

Habit Plants strongly rhizomatous, sometimes glaucous. Plants cespitose, often glaucous, not rhizomatous.
Culms

22-130 cm, erect;

nodes glabrous.

8-65 (77) cm, erect or geniculate to slightly decumbent, sometimes puberulent;

nodes 4-6, mostly concealed, usually glabrous, sometimes pubescent.

Leaves

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, scabrous, puberulent, or densely white-villous;

auricles usually present, to about 1 mm, often purplish;

ligules shorter than 1 mm, truncate, entire or lacerate;

blades (1)2-4(6) mm wide, spreading or ascending, often involute, sometimes folded, abaxial surfaces glabrous to puberulent, adaxial surfaces scabrous, puberulent, hirsute, or white-villous.

Spikes

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.

3-20 cm long, 5-15 cm wide, erect to sub-flexuous, with 2-3 spikelets per node, rarely with 1 at some nodes;

internodes 3-10(15) mm long, 0.1-0.4 mm thick at the thinnest sections, usually glabrous, sometimes puberulent beneath the spikelets.

Spikelets

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.

10-20 mm, divergent, sometimes glaucous, at least 1 spikelet at a node with 2-4(5) florets, 1-4(5) florets fertile, sometimes all florets sterile in the lateral spikelets;

disarticulation initially at the rachis nodes, subsequently beneath each floret.

Glumes

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.

subequal, 20-135 mm including the often undifferentiated awns, the bases indurate and glabrous, glume bodies 5-10 mm long, 1-3 mm wide, linear to setaceous, 1-3-veined, margins firm, awns 15-125 mm, scabrous, sometimes split into 2-3 unequal divisions, flexuous to outcurving from near the base at maturity;

fertile lemmas 6-12 mm, glabrous, scabrous, or appressed-pubescent, 2 lateral veins extending into bristles to 10 mm, awns 15-120 mm long, about 0.4 mm wide at the base, often reddish or purplish, scabrous, flexuous to curved near the base;

paleas 6-11 mm, veins often extending into bristles to 2(5) mm, apices acute to truncate;

anthers 0.9-2.2 mm.

Anthesis

from late May to July.

2n

= 28.

= 28.

Elymus lanceolatus

Elymus elymoides

Distribution
from FNA
AK; AZ; CA; CO; ID; IL; MI; MT; ND; NE; NM; NV; OR; SD; WA; WI; WY; AB; BC; MB; ON; SK; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; DC; ID; IL; KS; KY; MO; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; SK
[WildflowerSearch map]
[BONAP county map]
Discussion

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 elymoides grows in dry, often rocky, open woods, thickets, grasslands, and disturbed areas, from sagebrush deserts to alpine tundra. It is widespread in western North America, from British Columbia to northern Mexico and the western Great Plains, and introduced in western Missouri, Illinois, and Kentucky. It is often dominant in overgrazed pinyon-juniper woodlands. Although palatable early in the season, the disarticulating, long-awned spikes irritate grazing animals later in the year.

Elymus elymoides intergrades with E. multisetus (see previous) in parts of its southern range (Wilson 1963). It is sometimes confused with E. scribneri (p. 330), but differs in having more than one spikelet per node, narrower glumes, and less tardily disarticulating rachises. Hybrids with several other species in the Triticeae are known; they can often be recognized by their tardily disarticulating rachises. Named interspecific hybrids (pp. 338-343) (and the other parent) are E. xsaundersii (E. trachycaulus), E. xpinalenoensis (E. arizonicus), and possibly E. xhansenii (E. elymoides or E. multisetus x E. glaucus). Hybrids with E. sierrae have not been named; they are common where the two species are sympatric. They have broader glume bases, shorter glume awns, and longer anthers than E. elymoides.

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

Key
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
1. Rachis nodes with 3 spikelets, the central spikelet usually with 2 fertile florets, the florets of the lateral spikelets rudimentary to awnlike; lemma awns 15-30 mm long
subsp. hordeoides
1. Rachis nodes usually with 2 spikelets, each spikelet usually with (1)2-4(5) fertile florets; lemma awns 15-120 mm long.
→ 2
2. No spikelets appearing to have 3 glumes, the lowermost floret in each spikelet well developed; paleas rarely with the veins extended as bristles
subsp. brevifolius
2. One or more of the spikelets at most nodes appearing to have 3 glumes, the lowest 1-2 florets sterile and glumelike; paleas usually with the veins extended as bristles.
→ 3
3. Glumes with awns 15-70 mm long, all glumes entire
subsp. californicus
3. Glumes with awns 35-85 mm long, one of the glumes at most nodes with the awn split into 2 or 3 divisions
subsp. elymoides
Source FNA vol. 24, p. 327. FNA vol. 24, p. 318.
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. curvatus, E. dahuricus, E. diversiglumis, E. elymoides, E. glabriflorus, E. glaucus, E. hirsutus, E. hoffmannii, E. hystrix, E. interruptus, 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. 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. lanceolatus subsp. lanceolatus, E. lanceolatus subsp. psammophilus, E. lanceolatus subsp. riparius
E. elymoides subsp. brevifolius, E. elymoides subsp. californicus, E. elymoides subsp. elymoides, E. elymoides subsp. hordeoides
Synonyms Agropyron dasystachyum var. riparium, Agropyron dasystachyum Sitanion hystrix, E. pubiflorus, E. glaber, Sitanion longifolium, Sitanion pubiflorum
Name authority (Scribn. & J.G. Sm.) Gould (Raf.) Swezey
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