Elymus lanceolatus |
Elymus sierrae |
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streambank wheatgrass, streamside wild rye, thick-spike wildrye, thickspike wheatgrass |
Sierra wheatgrass, Sierra wildrye |
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Habit | Plants strongly rhizomatous, sometimes glaucous. | Plants cespitose, not rhizomatous. | ||||||||
Culms | 22-130 cm, erect; nodes glabrous. |
20-50 cm, prostrate or decumbent and geniculate; nodes 1-2, exposed, glabrous. |
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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. |
basally concentrated; sheaths glabrous; auricles usually present, to 1 mm on the lower leaves; ligules 0.2-0.5 mm, erose; blades 1-5 mm wide, flat, abaxial surfaces smooth, glabrous, adaxial surfaces prominently ridged over the veins, with scattered hairs, hairs to 0.2 mm, veins closely spaced. |
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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. |
5-15 cm long, 1.5-2.5 cm wide including the awns, 0.7-1.2 cm wide excluding the awns, flexuous, erect to nodding distally, with 1 spikelet at most nodes, occasionally some of the lower nodes with 2 spikelets; internodes 5-15 mm long, 0.2-0.5 mm wide, both surfaces glabrous, edges ciliate, not scabrous. |
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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. |
15-20 mm, ascending to divergent, with 3-7 florets; rachillas glabrous; disarticulation above the glumes, beneath each floret. |
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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, 6-9 mm long, 0.7-1 mm wide, lanceolate, glabrous, the bases evidently veined, apices entire, tapering into a 3-10 mm awn; lemmas 12-16 mm, glabrous, sometimes scabridulous, apices bidentate, awned, awns 15-30 mm, arcuately diverging to strongly recurved; paleas subequal to the lemmas, apices about 0.4 mm wide; anthers 2-3.5 mm. |
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2n | = 28. |
= 28. |
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Elymus lanceolatus |
Elymus sierrae |
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Distribution |
AK; AZ; CA; CO; ID; IL; MI; MT; ND; NE; NM; NV; OR; SD; WA; WI; WY; AB; BC; MB; ON; SK; YT
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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 sierrae is best known from rocky slopes and ridgetops in the Sierra Nevada, at 2100-3400 m, and is also found in Washington and Oregon. It resembles E. scribneri (see previous), differing in its non-disarticulating rachises, longer rachis internodes, and longer anthers. Hybrids with E. elymoides (p. 318) have glumes with awns 15+ mm long, and some spikelets with narrower glume bases and shorter anthers. Specimens with wide-margined glumes suggest hybridization with E. violaceus (p. 324). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 327. | FNA vol. 24, p. 332. | ||||||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | Poaceae > subfam. Pooideae > tribe Triticeae > Elymus | ||||||||
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Synonyms | Agropyron dasystachyum var. riparium, Agropyron dasystachyum | Agropyron pringlei | ||||||||
Name authority | (Scribn. & J.G. Sm.) Gould | Gould | ||||||||
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