Achnatherum parishii

(Vasey) Barkworth
Synonyms: Stipa parishii
Treatment appears in FNA Volume 24. Treatment on page 127.

Plants tightly cespitose, not rhizomatous. Culms 14-80 cm tall, 0.8-2 mm thick, internodes glabrous or pubescent below the nodes; nodes 3-5, glabrous. Basal sheaths mostly glabrous, sometimes pubescent at the base, flat and ribbonlike with age, margins sometimes hairy distally, hairs adjacent to the ligules 0.5-3 mm; collars glabrous; ligules truncate, abaxial surfaces pubescent, ciliate, cilia as long as or longer than the basal membrane, ligules of basal leaves 0.3-0.8 mm, of upper leaves 0.5-1.5 mm, asymmetric; blades 4-30+ cm long, 1-4.2 mm wide, usually flat and more or less straight, sometimes tightly convolute and arcuate. Panicles 7-15 cm long, 1.5-4 cm wide; branches strongly ascending at maturity, longest branches 1.5-4 cm. Glumes unequal to subequal, narrowly lanceolate, 3-5-veined; lower glumes 9-15 mm long, 0.9-1.2 mm wide; upper glumes 8-15 mm; florets 4.8-6.5 mm long, 0.8-1 mm thick, fusiform, terete; calluses 0.2-0.8 mm, acute; lemmas evenly and densely hairy, hairs 1.5-3.5 mm at midlength, apical hairs 2.5-5 mm; awns 10-35 mm, persistent, once-geniculate, first segment scabrous or strigose, hairs to 0.3 mm, terminal segment straight; paleas 2.5-4.5 mm, 1/2 - 4/5 times the length of the lemmas, hairy between the veins, hairs often as long as those on the lemmas but not as dense, apices usually rounded, occasionally somewhat pinched; anthers 2.3-4.5 mm, dehiscent, not penicillate. Caryopses 3-6 mm, fusiform. 2n = unknown.

Discussion

Achnatherum parishii grows from the coastal ranges of California to Nevada and Utah, south to Baja California, Mexico, and to the Grand Canyon in Arizona. It differs from A. coronatum in its once-geniculate awns, more densely pubescent paleas, and generally smaller stature; from A. scribneri in its shorter, blunter calluses and more abundant lemma hairs; and from A. perplexum in having longer hairs on its lemmas.

Selected References

None.

Key

1 Basal sheath margins glabrous or hairy distaily, hairs to 0.5 mm long; culms 14-35 cm tall Achnatherum parishii subsp. depauperatum
1 Basal sheath margins hairy distaily, hairs 1-3.2 mm long; culms 20-80 cm tall Achnatherum parishii subsp. parishii

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

... more about "Achnatherum parishii"
membranous +  and scarious +
not penicillate +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
awned +, bifid +, bilobed +  and entire +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Mary E. Barkworth +
(Vasey) Barkworth +
1 (?) +  and 3 (?) +
flexuous +
subterminal +  and eccentric +
usually scabrous +  and scabridulous +
once-geniculate +
1 cm10 mm <br />0.01 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
keeled +  and rounded +
pubescent +  and glabrous +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
straight +
4 cm40 mm <br />0.04 m <br /> (30 cm300 mm <br />0.3 m <br />) +
not evident +
involute +, convolute +  and flat +
1mm;4.2mm +
flexuous +  and straight +
spikelike +
well-developed +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
branching +  and not branching +
perennial +  and annual +
14 cm140 mm <br />0.14 m <br /> (80 cm800 mm <br />0.8 m <br />) +
intravaginal +  and basal +
10 cm100 mm <br />0.1 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
not woody +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Utah +, Calif. +, Ariz. +  and Nev. +
1/5 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.48 cm4.8 mm <br />0.0048 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
sometimes longer +
terete +  and fusiform +
1-10-veined +
subtending +
lanceolate +
unequal +  and subequal +
membranous +
uncinate +
0 cm0 mm <br />0 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
solid +  and hollow +
pubescent +  and glabrous +
basally concentrated +  and evenly distributed +
0 cm0 mm <br />0 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
ovate +, rectangular +  and lanceolate +
stiffly membranous +  and coriaceous +
asymmetric +  and truncate +
pubescent +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
membranous +
membranous +
inconspicuous +
not lobed +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.9mm +  and 1.2mm +
concealed +  and prominent +
3 +  and 5 +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
not keeled +
reduced +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
7cm +  and 15cm +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
dry +  and fleshy +
not prolonged +
1 +  and 60 +
unisexual +  and bisexual +
laterally compressed +  and terete +
1 (?) +  and 3 (?) +
simple +  and compound +
Stipa parishii +
Achnatherum parishii +
Achnatherum +
species +
membranous +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 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 +