Nassella cernua

(Stebbins & Love) Barkworth
Common names: Cernuous nassella Nodding needlegrass
Synonyms: Stipa cernua
Treatment appears in FNA Volume 24. Treatment on page 176.

Plants perennial; cespitose, not rhizomatous. Culms 30-100 cm tall, 1-2.2 mm thick, erect or geniculate at the basal nodes, internodes pubescent below the nodes, lowest internodes sometimes pubescent throughout; nodes 2-3, glabrous. Leaves usually glaucous; sheaths mostly glabrous, throats ciliate; collars mostly glabrous, with sparse tufts of hair at the sides, hairs 1-1.6 mm; ligules 0.2-1.6 mm, glabrous, truncate to rounded; blades 3-26 cm long, 0.4-1.2 mm wide, flat to convolute, abaxial surfaces scabridulous, adaxial surfaces hairy. Panicles 15-80 cm, open, often partially enclosed at maturity; branches 1-6 cm, flexuous or cernuous, with 1-8 spikelets on the distal 1/2; pedicels 3-9 mm. Glumes glabrous, narrowly lanceolate, acuminate; lower glumes 12-22 mm long, 0.9-1.7 mm wide; upper glumes 3-4 mm shorter that the lower glumes; florets 4-9 mm long, 0.6-0.8 mm wide, terete; calluses 1.4-3.6 mm, sharp, strigose; lemmas minutely papillose, tapering to the crown, the proximal 1/4 evenly pubescent, the distal 3/4 pubescent only over the veins; crowns 0.2-0.5 mm long, 0.3-0.35 mm wide, straight-sided, rims with 0.8-1.1 mm hairs; awns 50-110 mm long, 0.2-0.3 mm thick at the base, first geniculation evident, second geniculation obscure, terminal segment cernuous; anthers 3.5-5.5 mm, penicillate. Caryopses 4.5-5.5 mm. 2n = 70.

Distribution

Calif., Pacific Islands (Hawaii)

Discussion

Nassella cernua grows in grasslands, chaparral, and juniper associations of the inner coast ranges of California and Baja California, Mexico. Small specimens resemble N. lepida, but have longer and thicker awns and fewer florets. Large specimens resemble N. pulchra, but have thinner awns with cernuous, rather than straight, terminal segments. It is superficially similar to Achnatherum eminens, but differs in its shorter ligules, strongly overlapping lemma margins, glabrous paleas, and geographic distribution.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Nassella cernua"
membranous +  and scarious +
3 +  and 1 +
penicillate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
awned +, bifid +, bilobed +  and entire +
not lobed +, not sharp +, narrowly acute +  and acute +
Mary E. Barkworth +
(Stebbins & Love) Barkworth +
twisted +  and not branched +
1 (?) +  and 3 (?) +
5 cm50 mm <br />0.05 m <br /> (11 cm110 mm <br />0.11 m <br />) +
eccentric +
obscure +  and evident +
0.3 cm3 mm <br />0.003 m <br /> (30 cm300 mm <br />0.3 m <br />) +
keeled +  and rounded +
pale color +
intravaginal +, extravaginal +, branching +  and basal +
constricted +
3 cm30 mm <br />0.03 m <br /> (26 cm260 mm <br />0.26 m <br />) +
not evident +
flat +  and convolute +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
spikelike +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
well-developed +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.36 cm3.6 mm <br />0.0036 m <br />) +
Cernuous nassella +  and Nodding needlegrass +
straight-sided +
0.2mm +  and 0.5mm +
perennial +  and annual +
30 cm300 mm <br />0.3 m <br /> (100 cm1,000 mm <br />1 m <br />) +
geniculate +
10 cm100 mm <br />0.1 m <br /> (175 cm1,750 mm <br />1.75 m <br />) +
not woody +
0.1 cm1 mm <br />0.001 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
Calif. +  and Pacific Islands (Hawaii) +
0 +  and 2/5 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
sometimes longer +
0.6mm +  and 0.8mm +
1-10-veined +
subtending +
acuminate +  and lanceolate +
membranous +
uncinate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
solid +  and hollow +
basally concentrated +  and evenly distributed +
3 cm30 mm <br />0.03 m <br /> (60 cm600 mm <br />0.6 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
3/4 +  and 1/4 +
papillose +
tapering +
membranous +  and coriaceous or indurate +
truncate +  and rounded +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
membranous +
inconspicuous +
lanceolate +
fleshy +  and membranous +
1.2 cm12 mm <br />0.012 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.9mm +  and 1.7mm +
concealed +  and prominent +
2 +  and 3 +
2 +  and 1 +
well-developed +
0 +  and 1/2 +
reduced +
15 cm150 mm <br />0.15 m <br /> (80 cm800 mm <br />0.8 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
dry +  and fleshy +
not prolonged +
unisexual +  and bisexual +
laterally compressed +  and terete +
0.3 cm3 mm <br />0.003 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Stipa cernua +
Nassella cernua +
Nassella +
species +
membranous +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
inconspicuous +
plant +  and cespitose +
aquatic +  and terrestrial +