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

Baker's wheatgrass

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

22-130 cm, erect;

nodes glabrous.

30-50 cm tall, 1-2 mm thick, ascending to erect;

nodes glabrous.

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.

not basally concentrated;

sheaths glabrous;

auricles 0.3-0.6 mm;

ligules 0.5-1 mm;

blades 12-20 cm long, 2-4 mm wide, stiff, abaxial surfaces smooth, glabrous, adaxial surfaces smooth or scabridulous, veins prominent, closely spaced.

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.

8-12 cm long, 4-6 cm wide including the awns, about 1 cm wide excluding the awns, straight, erect or inclined, with 1 spikelet per node;

internodes 5-9 mm long, about 0.8 mm wide, both surfaces glabrous, edges ciliate.

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.

10-19 mm long, about twice as long as the adjacent internodes, 4-10 mm wide, appressed, with 4-5 florets;

rachillas scabrous or hirtellous;

disarticulation above the glumes, 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.

7-12 mm long, 1.4-2 mm wide, narrowly oblong, usually green or green tinged with purple, the bases evidently veined or indurate for less than 0.5 mm, 5-veined, veins scabrous, margins narrow, widest distally, apices acute, sometimes bifid, awned, awns 2-8 mm, straight or divergent;

lemmas scabrous or smooth, apices often shortly bidentate, awns 10-35 mm, arcuate to recurved;

paleas equaling or slightly longer than the lemmas, tapering to the 0.2-0.4 mm wide apices;

anthers 0.8-1.5 mm.

2n

= 28.

= 28.

Elymus lanceolatus

Elymus bakeri

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
CO; ID; MT; NM; OR; UT; WA; WY
[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 bakeri grows in high, but not alpine, mountain meadows of Colorado and northern New Mexico. It resembles the awned phase of Pseudoroegneria spicata (p. 281), but differs in having rather thicker culms and spikes, and stouter lemma awns. W.A. Weber (University of Colorado, pers. comm., ca. 1999) stated that it often forms large stands in Colorado.

Reports of Elymus bakeri from Idaho appear to be based on fertile hybrids of E. trachycaulus (p. 321) or E. violaceus (p. 324) with Pseudoroegneria spicata; that for Wallowa County, Oregon, on a specimen of E. glaucus (p. 306).

(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
Source FNA vol. 24, p. 327. FNA vol. 24, p. 330.
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. 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. 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
Synonyms Agropyron dasystachyum var. riparium, Agropyron dasystachyum E. trachycaulus subsp. bakeri, Agropyron bakeri
Name authority (Scribn. & J.G. Sm.) Gould (E.E. Nelson) Á. Löve
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