Elymus alaskanus

(Scribn. & Merr.) Á.Löve
Synonyms: Roegneria villosa Roegneria borealis Elymus alaskanus subsp. borealis Agropyron alaskanum
Treatment appears in FNA Volume 24. Treatment on page 326.

Plants cespitose or weakly rhizomatous. Culms 20-90 cm, sometimes decumbent at the base, ascending to erect above; nodes usually pubescent, sometimes glabrous. Leaves sometimes basally concentrated; sheaths smooth or scabrous, glabrous or pilose; auricles absent or to 0.5 mm; ligules 0.2-1 mm, erose, ciliolate; blades 3-7 mm wide, flat, both surfaces smooth, scabrous, or pubescent. Spikes 3.5-14 cm long, 0.5-0.8 cm wide, erect or nodding distally, usually with 1 spikelet per node, occasionally with 2 at the lower nodes; internodes 3-10 mm long, 0.5-0.8 mm wide, mostly glabrous and smooth, edges scabrous or ciliate. Spikelets 9-15 (20) mm, 2-5 times longer than the internodes, appressed, with 3-6 florets, rachillas hispidulous; disarticulation above the glumes, beneath each floret. Glumes 4-8 mm long, (1.2) 1.5-2 mm wide, 1/3-2/3 as long as the adjacent lemmas, oblanceolate to obovate, flat, usually purplish, glabrous or hairy, hairs 0.3-0.5 mm, margins unequal, the widest margin 0.4-1 mm wide, both margins widest above the middle, apices unawned or awned, awns to 1 mm; lemmas 7-11 mm, glabrous or hairy, sometimes scabridulous, sometimes more densely hairy distally, hairs 0.2-0.6 mm, all alike, apices unawned or awned, awns to 7 mm, straight; paleas subequal to the lemmas, keels straight below the apices; anthers 1-2 mm. 2n = 28.

Distribution

Alta., B.C., Greenland, Nfld. and Labr. (Nfld.), Man., N.S., N.W.T., Nunavut, Ont., Que., Yukon, Mont., Wyo., Colo., N.Mex., Wash., Idaho, Mich., Alaska, Oreg., Nev.

Discussion

Elymus alaskanus extends across the high arctic of North America to extreme eastern Russia. This treatment interprets E. alaskanus as having relatively short glumes, in accordance with its treatment by Hulten (1968). Large specimens resemble E. macrourus (see previous), but differ in the shape of their glumes and in their wider glume margins. Elymus alaskanus differs from E. trachycaulus (p. 321) in its greater cold tolerance and the distal widening of its glume margins. There is some intergradation, particularly with E. violaceus (p. 324) and E. trachycaulus, but these species have longer glumes. Moreover, in western North America, E. violaceus is restricted to rocky habitats at or above treeline, whereas E. alaskanus is often associated with valleys and flat areas. Reports of its extending to New Mexico are based on the inclusion of high-elevation forms of E. trachycaulus.

Selected References

None.

Key

1 Glumes glabrous, scabrous or sparsely hairy, hairs to about 0.2 mm long; lemmas glabrous or with hairs to about 0.2 mm long Elymus alaskanus subsp. alaskanus
1 Glumes and lemmas densely hairy, hairs 0.2-0.5 mm long Elymus alaskanus subsp. hyperarcticus

"decumbent" is not a number.

... more about "Elymus alaskanus"
membranous +  and scarious +
with hairs +  and scabrous +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
bidentate +  and acute +
Mary E. Barkworth +, Julian J.N. Campbell +  and Bjorn Salomon +
(Scribn. & Merr.) Á.Löve +
1 (?) +  and 3 (?) +
straight +
basal +  and apical +
from the sinus +  and terminal +
not geniculate +
0 cm0 mm <br />0 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
cross +, linear +  and narrowly lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
spikelike +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
hairy +  and glabrous +
not branching +
ascending +  and erect +
20 cm200 mm <br />0.2 m <br /> (90 cm900 mm <br />0.9 m <br />) +
not woody +
Alta. +, B.C. +, Greenland +, Nfld. and Labr. (Nfld.) +, Man. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, Que. +, Yukon +, Mont. +, Wyo. +, Colo. +, N.Mex. +, Wash. +, Idaho +, Mich. +, Alaska +, Oreg. +  and Nev. +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
3 +  and 6 +
laterally compressed +  and terete +
(0)1-7-veined +
shorter than to longer than the adjacent florets +
4mm +  and 8mm +
subtending +
hairy +  and glabrous +
1/3 +  and 2/3 +
oblanceolate +  and obovate +
unequal +, subequal +  and reduced +
1.5mm +  and 2mm +
uncinate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
solid +  and hollow +
1.5 cm15 mm <br />0.015 m <br /> (?) +
3mm +  and 10mm +
0.2 cm2 mm <br />0.002 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +  and 0.08 cm0.8 mm <br />8.0e-4 m <br /> (?) +
ciliate +  and scabrous +
distributed +
hairy +  and glabrous +
scabridulous +
linear-lanceolate +
0.7 cm7 mm <br />0.007 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
stiffly membranous +  and coriaceous +
erose +  and entire +
acute +, rounded +  and truncate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
membranous +
inconspicuous +
lanceolate +
fleshy +  and membranous +
concealed +  and prominent +
glabrous +  and pubescent +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
slightly longer +
subequal +
dry +  and fleshy +
spikelike +
pilose +, glabrous +, scabrous +  and smooth +
3.5 cm35 mm <br />0.035 m <br /> (?) +  and 14 cm140 mm <br />0.14 m <br /> (?) +
subsessile +  and sessile +
2-5 times longer than +
bisexual +  and sterile +
terete +  and compressed +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
pubescent +, scabrous +  and smooth +
not papillate +
Roegneria villosa +, Roegneria borealis +, Elymus alaskanus subsp. borealis +  and Agropyron alaskanum +
Elymus alaskanus +
species +
membranous +
0 cm0 mm <br />0 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
inconspicuous +
unequal +
plant +  and cespitose +
aquatic +  and terrestrial +