Achnatherum latiglume

(Swallen) Barkworth
Common names: Wide-glumed needlegrass
Endemic
Synonyms: Stipa latiglumis
Treatment appears in FNA Volume 24. Treatment on page 124.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants tightly cespitose, not rhizomatous. Culms 50-110 cm tall, 0.7-1.2 mm thick, lower internodes retrorsely pilose, upper internodes glabrous; nodes 2-4. Basal sheaths usually retrorsely pubescent, brown to gray-brown, flat when mature; collars usually glabrous, sometimes with a few hairs at the sides; basal ligules 0.2-2.5 mm, truncate to rounded; upper ligules 1.2-3 mm, rounded to acute, ciliate; blades 0.7-3 mm wide, straight to lax, abaxial surfaces smooth, glabrous, adaxial surfaces pubescent, scabrous. Panicles 15-30 cm long, 0.8-2 cm wide; branches appressed to strongly ascending, longest branches 2.5-6.5 cm. Glumes subequal, 12-15 mm long, 1.3-1.9 mm wide, 3-veined; florets 8-9 mm long, 0.9-1.4 mm thick, fusiform, terete; calluses 0.7-1 mm, blunt to sharp; lemmas evenly hairy, hairs 0.5-1.5 mm at midlength, apical hairs 1-2 mm, apical lobes to 1 mm, membranous; awns 33-45 mm, persistent, twice-geniculate, first 2 segments pilose, with hairs 0.5-2 mm, terminal segment mostly scabrous, straight; paleas 4-5 mm, 3/5 – 4/5 as long as the lemmas, pubescent; anthers not seen. Caryopses not seen. 2n = 70.

Discussion

Achnatherum latiglume usually grows on dry slopes in yellow pine forests of southern California. Pohl (1954) demonstrated that it is an alloploid derivative of A. nelsonii and A. lemmonii. He reported being told that it was a fairly common species in the Yosemite Valley, and suggested that the isolated occurrences in Riverside and Fresno counties might represent separate origins of the species.

Achnatherum latiglume resembles A. nevadense and A. occidental, but the latter two species have sharper calluses, and their paleas tend to be thinner and somewhat shorter relative to the lemmas than those of A. latiglume.

Selected References

None.

Lower Taxa

None.

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

... more about "Achnatherum latiglume"
membranous +  and scarious +
penicillate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
awned +, bifid +, bilobed +  and entire +
Rounded (?) +  and Acute (?) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Mary E. Barkworth +
(Swallen) Barkworth +
1 (?) +  and 3 (?) +
flexuous +
subterminal +  and eccentric +
usually scabrous +  and scabridulous +
not once-geniculate +
3.3 cm33 mm <br />0.033 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
keeled +  and rounded +
brown +  and gray-brown +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
straight +
not evident +
involute +, convolute +  and flat +
0.7mm;3mm +
flexuous +  and straight +
appressed;strongly ascending +
spikelike +
well-developed +
blunt +  and sharp +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Wide-glumed needlegrass +
branching +  and not branching +
perennial +  and annual +
50 cm500 mm <br />0.5 m <br /> (110 cm1,100 mm <br />1.1 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 /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
1/5 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.8 cm8 mm <br />0.008 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
sometimes longer +
terete +  and fusiform +
12mm +  and 15mm +
subtending +
obtuse +, acute +  and acuminate +
subequal +
membranous +
1.3mm +  and 1.9mm +
divergent +  and distributed +
uncinate +
0.05 cm0.5 mm <br />5.0e-4 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 +
pubescent +  and glabrous +
membranous +
membranous +
inconspicuous +
not lobed +
2.5 cm25 mm <br />0.025 m <br /> (6.5 cm65 mm <br />0.065 m <br />) +
concealed +  and prominent +
2 +  and 4 +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
3/5 +  and 4/5 +
not keeled +
reduced +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
15cm +  and 30cm +
0.8 cm8 mm <br />0.008 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 latiglumis +
Achnatherum latiglume +
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 +