Leymus mollis

(Trin.) Pilg.
Common names: American dunegrass Sea lymegrass Elyme des sables d'amerique Seigle de mer
Synonyms: Elymus mollis Elymus arenarius var. villosus Elymus arenarius var. mollis Elymus arenarius subsp. mollis
Treatment appears in FNA Volume 24. Treatment on page 356.

Plants not cespitose, strongly rhizomatous, occasionally slight¬ly glaucous. Culms 12-170 cm tall, 3-6 mm thick, usually densely pubescent below the spikes for 10-40+ mm. Leaves exceeded by the spikes; auricles to 0.7 mm; ligules 0.2-2.5 mm; blades 10-94 cm long, 3-15 mm wide, adaxial surfaces scabridulous to scabrous, 20-40-veined, veins subequal, prominently ribbed, closely spaced. Spikes 5-34 cm long, 10-20 mm wide, with 3-33 nodes, usually with 2 spikelets per node; internodes 4.5-9.5 mm, surfaces and edges similar, hairs on the surfaces 0.1-0.5 mm, on the edges to 0.7 mm. Spikelets 15-34 mm, with 3-6 florets. Glumes 9-34 mm long, 1.5-4 mm wide, lanceolate, tapering from midlength or above, flat or rounded on the back, flexible, usually strigillose to pilose or villous, rarely almost glabrous, the central portion scarcely thicker than the margins, 3 (5) -veined at midlength, apices acute; lemmas 11-20 mm, densely hairy, hairs 0.5-1 mm, soft, apices acute, unawned; anthers 4-9 mm, dehiscent.

Distribution

Alta., B.C., Greenland, Man., N.B., Nfld. and Labr., N.S., N.W.T., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Maine, Mass., Wash., Alaska, Mich., Wis., Oreg., N.H., Pa., Ill., Calif.

Discussion

Leymus mollis is native to Asia and North America. It is treated here as having two very similar subspecies that have somewhat different ranges. The subspecies are sometimes treated as separate species, but they may be little more than environmentally induced variants. Both subspecies grow primarily on coastal beaches, close to the high tide line, and along some inland waterways, particularly in the arctic. Reports of L. ajanensis (V.N. Vassil.) Tzvelev from North America are based on specimens of L. mollis (D. Murray, University of Alaska, pers. comm. 2006).

Selected References

None.

Key

1 Spikes 12-34 cm long, with 12-33 nodes; basal blades 5-15 mm wide; culms 50-170 cm tall Leymus mollis subsp. mollis
1 Spikes 5-13(16) cm long, with 3-14 nodes; basal blades 3-8 mm wide; culms 12-70 cm tall Leymus mollis subsp. villosissimus

"decumbent" is not a number."/2-33/4timesthelengthof" is not declared as a valid unit of measurement for this property.

... more about "Leymus mollis"
membranous +  and scarious +
scabridulous +  and scabrous +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0-3(7)-veined +
straight +
midlength +
hairy +, glabrous +  and pilose +
0 cm0 mm <br />0 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0 cm0 mm <br />0 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
Mary E. Barkworth +
(Trin.) Pilg. +
0-3(7)-veined +
1 (?) +  and 3 (?) +
straight +
midlength +
glabrous +  and pilose +
tapering +, acuminate +, acute +  and keeled +
1.6 cm16 mm <br />0.016 m <br /> (3.3 cm33 mm <br />0.033 m <br />) +
rounded +  and flat +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
10 cm100 mm <br />0.1 m <br /> (94 cm940 mm <br />0.94 m <br />) +
not evident +
cross +, linear +  and narrowly lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
spikelike +
hairy +  and glabrous +
American dunegrass +, Sea lymegrass +, Elyme des sables d'amerique +  and Seigle de mer +
not branching +
12 cm120 mm <br />0.12 m <br /> (170 cm1,700 mm <br />1.7 m <br />) +
10 cm100 mm <br />0.1 m <br /> (350 cm3,500 mm <br />3.5 m <br />) +
not woody +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Alta. +, B.C. +, Greenland +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +, Yukon +, Maine +, Mass. +, Wash. +, Alaska +, Mich. +, Wis. +, Oreg. +, N.H. +, Pa. +, Ill. +  and Calif. +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
3 +  and 6 +
laterally compressed +  and terete +
shorter than to longer than the adjacent florets +
9mm +  and 34mm +
subtending +
glabrous +, usually strigillose +  and pilose or villous +
tapering +  and lanceolate +
reduced +  and subequal +
1.5mm +  and 4mm +
uncinate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
solid +  and hollow +
15 cm150 mm <br />0.15 m <br /> (?) +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.95 cm9.5 mm <br />0.0095 m <br />) +
0-3(7)-veined +
glabrous +  and pilose +
tapering +, acuminate +, acute +  and keeled +
distributed +
keeled +  and rounded +
1.1 cm11 mm <br />0.011 m <br /> (2 cm20 mm <br />0.02 m <br />) +
stiffly membranous +  and coriaceous +
truncate +  and rounded +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
membranous +
inconspicuous +
fleshy +  and membranous +
concealed +  and prominent +
3 +  and 33 +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
slightly shorter than to slightly longer than the lemmas +
slightly longer +
subequal +
appressed +  and ascending +
0 cm0 mm <br />0 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
dry +  and fleshy +
spikelike +
5 cm50 mm <br />0.05 m <br /> (?) +  and 34 cm340 mm <br />0.34 m <br /> (?) +
pedicellate +  and sessile +
bisexual +  and sterile +
terete +  and compressed +
1.5 cm15 mm <br />0.015 m <br /> (3.4 cm34 mm <br />0.034 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
not papillate +
Elymus mollis +, Elymus arenarius var. villosus +, Elymus arenarius var. mollis +  and Elymus arenarius subsp. mollis +
Leymus mollis +
species +
awnlike +
membranous +
0-3(7)-veined +
midlength +
glabrous +  and pilose +
tapering +, acuminate +, acute +  and keeled +
subequal +
0 cm0 mm <br />0 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
plant +  and not cespitose +
aquatic +  and terrestrial +