Achnatherum wallowaense

J.R. Maze & K.A. Robson
Common names: Wallowa needlegrass
Treatment appears in FNA Volume 24. Treatment on page 138.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants tightly cespitose, not rhizomatous. Culms (10) 15-40 (45) cm tall, 0.5-0.7 mm thick, glabrous; nodes 1-2. Basal sheaths becoming flat with age, glabrous; collars glabrous, including the sides; basal ligules 0.8-1.3 mm, membranous, truncate to broadly acute, glabrous; upper ligules to 1.6 mm; blades tightly valvate to involute, 0.5-0.8 mm in diameter, abaxial surfaces scabridulous, adaxial surfaces hairy, sometimes densely hairy, hairs shorter than 0.05 mm. Panicles (4) 5-13 (15) cm long, to 10 cm wide, lax; branches divergent, flexuous, longest branches 2-10 cm, with spikelets confined to the distal portions, drooping. Glumes obtuse to acute; lower glumes 3.5-7 mm long, 0.8-1.3 mm wide, 5 (7) -veined; upper glumes 3-6.5 mm, 3-veined; florets 3-5.5 mm long, 1-1.5 mm thick, fusiform, terete; calluses 0.1-0.2 mm, blunt; lemmas coriaceous, shiny, glabrous, black to dark-brown at maturity, margins overlapping at maturity, apices thickened dorsally; awns 5-11 mm, readily deciduous, not or weakly geniculate, scabrous; paleas 2.8-4.5 mm, similar to the lemmas in texture, glabrous; anthers 1.6-1.8 mm, dehiscent, not penicillate. Caryopses 2-4 mm, ovoid. 2n = unknown.

Discussion

Achnatherum wallowaense grows in shallow, rocky soil at scattered localities, from 1000-1600 m, in the Wallowa and Ochoco mountains, Oregon.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number."prolonged" is not a number.

... more about "Achnatherum wallowaense"
membranous +  and scarious +
not penicillate +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
awned +, bifid +, bilobed +  and entire +
Rounded (?) +  and Acute (?) +
0 cm0 mm <br />0 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Mary E. Barkworth +
J.R. Maze & K.A. Robson +
1 (?) +  and 3 (?) +
flexuous +
subterminal +  and eccentric +
usually scabrous +  and scabridulous +
geniculate +
0.5 cm5 mm <br />0.005 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
involute +, convolute +  and flat +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
spikelike +
well-developed +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
Wallowa needlegrass +
branching +  and not branching +
perennial +  and annual +
15 cm150 mm <br />0.15 m <br /> (40 cm400 mm <br />0.4 m <br />) +
intravaginal +  and basal +
10 cm100 mm <br />0.1 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
not woody +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
1/5 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.3 cm3 mm <br />0.003 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
sometimes longer +
terete +  and fusiform +
1-10-veined +
subtending +
obtuse +  and acute +
membranous +
divergent +  and distributed +
uncinate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +
solid +  and hollow +
basally concentrated +  and evenly distributed +
0 cm0 mm <br />0 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
black +  and dark-brown +
ovate +, rectangular +  and lanceolate +
coriaceous +
pubescent +  and glabrous +
membranous +
membranous +
inconspicuous +
not lobed +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.8mm +  and 1.3mm +
concealed +  and prominent +
1 +  and 2 +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
not keeled +
reduced +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
5cm +  and 13cm +
0 cm0 mm <br />0 m <br /> (10 cm100 mm <br />0.1 m <br />) +
dry +  and fleshy +
not prolonged +
1 +  and 60 +
unisexual +  and bisexual +
laterally compressed +  and terete +
1 (?) +  and 3 (?) +
simple +  and compound +
Gramineae +
Achnatherum wallowaense +
Achnatherum +
species +
membranous +
0.3 cm3 mm <br />0.003 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
inconspicuous +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
plant +  and cespitose +
aquatic +  and terrestrial +