Psathyrostachys juncea

(Fisch.) Nevski
Common names: Russian wildrye
Synonyms: Elymus junceus
Treatment appears in FNA Volume 24. Treatment on page 372.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants densely cespitose. Culms (20) 30-80 (120) cm, erect or decumbent at the base, mostly glabrous, pubescent below the spikes. Basal sheaths glabrous, grayish-brown, old sheaths more or less persistent; auricles 0.2-1.5 mm; blades (1) 2.5-18 (30) cm long, (1) 5-20 mm wide, flat or involute, abaxial surfaces smooth or scabridulous, often glaucous. Spikes (3) 6-11 (16) cm long, 5-17 mm wide, erect, with (2) 3 spikelets per node; rachises hirsute on the margins, puberulent elsewhere; internodes 3.5-6 mm. Spikelets 7-10 (12) mm excluding the awns, strongly overlapping, lateral spikelets slightly larger than the central spikelets. Glumes (3.5) 4.2-9.4 mm, subulate, scabrous or with 0.3-0.8 mm hairs; lemmas 5.5-7.5 mm, lanceolate, glabrous or with 0.3-0.8 mm hairs, sharply acute or awned, awns 0.8-3.5 mm; paleas 5.8-7.6 mm, scabrous, acute; anthers 2.5-5.1 mm; lodicules 1.3-1.5 mm. Caryopses 4.3-5 mm. 2n = 14, rarely 28.

Distribution

Minn., Colo., N.Mex., Tex., Utah, Alaska, Alta., Man., Sask., Yukon, Mont., Wyo., Wash., Ariz., N.Dak., Nebr., S.Dak.

Discussion

Psathyrostachys juncea is native to central Asia, primarily to the Russian and Mongolian steppes. It has become established at various locations, from Alaska to Arizona and New Mexico. It is drought-resistant and tolerant of saline soils. In its native range, it grows on stony slopes and roadsides, at elevations to 5500 m.

Psathyrostachys juncea closely resembles Leymus cinereus, differing primarily in having shorter ligules and a rachis that breaks up at maturity. Immature plants can be identified by the more uniform appearance of the spikelets. Psathyrostachys juncea also tends to have smaller spikelets with fewer florets than L. cinereus. Plants with pilose florets have been treated as a distinct taxon; such recognition is not merited.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Psathyrostachys juncea"
scabridulous +  and smooth +
membranous +  and scarious +
7 cm70 mm <br />0.07 m <br /> (?) +
violet +  and yellow +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.51 cm5.1 mm <br />0.0051 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Claus Badenf +
(Fisch.) Nevski +
1 (?) +  and 3 (?) +
violet-tinged +
straight +
basal +  and apical +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
2.5 cm25 mm <br />0.025 m <br /> (18 cm180 mm <br />0.18 m <br />) +
not evident +
involute +  and flat +
5mm;20mm +
spikelike +
hairy +  and glabrous +
Russian wildrye +
not branching +
decumbent +  and erect +
pubescent +  and glabrous +
30 cm300 mm <br />0.3 m <br /> (80 cm800 mm <br />0.8 m <br />) +
not woody +
Minn. +, Colo. +, N.Mex. +, Tex. +, Utah +, Alaska +, Alta. +, Man. +, Sask. +, Yukon +, Mont. +, Wyo. +, Wash. +, Ariz. +, N.Dak. +, Nebr. +  and S.Dak. +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
additional +, 1 +  and 2 +
laterally compressed +  and terete +
reduced +
shorter than to longer than the adjacent florets +
subtending +
scabrous +  and pubescent +
with 0.3-0.8 mm hairs +  and scabrous +
subulate +
unequal +
0.42 cm4.2 mm <br />0.0042 m <br /> (0.94 cm9.4 mm <br />0.0094 m <br />) +
uncinate +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
solid +  and hollow +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
with 0.3-0.8 mm hairs +  and glabrous +
awned +, acute +  and lanceolate +
0.55 cm5.5 mm <br />0.0055 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
stiffly membranous +  and coriaceous +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
membranous +
inconspicuous +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
fleshy +  and membranous +
concealed +  and prominent +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
slightly longer +
pilose +  and scabrous +
subequal +
0.58 cm5.8 mm <br />0.0058 m <br /> (0.76 cm7.6 mm <br />0.0076 m <br />) +
membranous +
dry +  and fleshy +
spikelike +
puberulent +  and hirsute +
persistent +
fibrillose +
6 cm60 mm <br />0.06 m <br /> (?) +  and 11 cm110 mm <br />0.11 m <br /> (?) +
subsessile +  and sessile +
bisexual +  and sterile +
terete +  and compressed +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1 (?) +  and 3 (?) +
simple +  and compound +
2 (?) +  and 3 (?) +
not papillate +
Elymus junceus +
Psathyrostachys juncea +
Psathyrostachys +
species +
membranous +
rhizomatous +  and stoloniferous +
plant +  and cespitose +
aquatic +  and terrestrial +