Achnatherum curvifolium

(Swallen) Barkworth
Common names: Curlyleaf needlegrass
Synonyms: Stipa curvifolia
Treatment appears in FNA Volume 24. Treatment on page 135.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants tightly cespitose, not rhizomatous. Culms 25-55 cm tall, 0.7-1 mm thick, glabrous; nodes 3. Basal sheaths usually puberulent, hairs 0.1-0.2 mm, sometimes densely tomentose at the base, brown to gray-brown when old; collars glabrous, sometimes with tufts of hair on the sides, hairs to 0.5 mm; ligules truncate, pubescent, hairs about 0.1; basal ligules about 0.3 mm, upper ligules to 0.6 mm; blades normally valvate to involute, about 0.5 mm in diameter, strongly arcuate, abaxial surfaces pubescent near the base, glabrous and smooth distally, adaxial surfaces densely hairy, hairs to 0.2 mm. Panicles 7-11 cm long, 1-2 cm wide; branches appressed to strongly ascending, longest branches 3-4 cm. Glumes subequal, 10-14 mm long, 0.7-0.9 mm wide; florets 6-8 mm long, 0.4-0.8 mm thick, fusiform, terete; calluses 1-1.5 mm, sharp; lemmas evenly hairy, hairs at midlength 0.3-1 mm, apical hairs 1-1.5 mm, apical lobes not developed; awns 22-38 mm, once-geniculate, first segment pubescent, hairs 1-2 mm, gradually decreasing in length distally; paleas 2-2.3 mm, 1/4-1/3 as long as the lemmas, glabrous; anthers about 3.5 mm, dehiscent, not penicillate. Caryopses about 4 mm, fusiform. 2n = 44.

Discussion

Achnatherum curvifolium grows on cliffs and in disturbed, rocky, limestone habitats. It is known from relatively few locations in the Flora region; it is more common in northern Mexico. It is most readily distinguished from other species of Achnatherum in the Flora region by its combination of curly leaves and hairy awns.

Selected References

None.

Lower Taxa

None.

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

... more about "Achnatherum curvifolium"
membranous +  and scarious +
not penicillate +
3.5 cm35 mm <br />0.035 m <br /> (?) +
awned +, bifid +, bilobed +  and entire +
rounded +  and acute +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Mary E. Barkworth +
(Swallen) Barkworth +
1 (?) +  and 3 (?) +
flexuous +
subterminal +  and eccentric +
usually scabrous +  and scabridulous +
once-geniculate +
2.2 cm22 mm <br />0.022 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
involute +, convolute +  and flat +
0.5 cm5 mm <br />0.005 m <br /> (?) +
flexuous +  and straight +
appressed;strongly ascending +
spikelike +
well-developed +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Curlyleaf needlegrass +
branching +  and not branching +
perennial +  and annual +
25 cm250 mm <br />0.25 m <br /> (55 cm550 mm <br />0.55 m <br />) +
intravaginal +  and basal +
10 cm100 mm <br />0.1 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
not woody +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
N.Mex. +  and Tex. +
1/5 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
sometimes longer +
terete +  and fusiform +
10mm +  and 14mm +
subtending +
obtuse +, acute +  and acuminate +
subequal +
membranous +
0.7mm +  and 0.9mm +
divergent +  and distributed +
brown +  and gray-brown +
decreasing +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 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 />) +
ovate +, rectangular +  and lanceolate +
stiffly membranous +  and coriaceous +
membranous +
membranous +
inconspicuous +
not lobed +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
concealed +  and prominent +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
1/4 +  and 1/3 +
not keeled +
reduced +
0.2 cm2 mm <br />0.002 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
7cm +  and 11cm +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
dry +  and fleshy +
not prolonged +
1 +  and 60 +
unisexual +  and bisexual +
laterally compressed +  and terete +
1 +  and 3 +
simple +  and compound +
Stipa curvifolia +
Achnatherum curvifolium +
Achnatherum +
species +
membranous +
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 +