Nassella trichotoma |
Nassella pulchra |
|
---|---|---|
serrated tussock, serrated tussockgrass, yass tussockgrass |
purple nassella, purple needlegrass, purple tussockgrass |
|
Habit | Plants perennial; cespitose, not rhizomatous. | Plants perennial; cespitose, not rhizomatous. |
Culms | 20-60 cm tall, about 1 mm thick, erect, internodes glabrous; nodes 2-4, pubescent. |
35-100 cm tall, 1.8-3.1 mm thick, erect or geniculate at the lowest nodes, sometimes scabrous below the panicles, internodes mostly glabrous, lower internodes sometimes pubescent below the nodes; nodes 2-3, pubescent. |
Sheaths | glabrous, smooth; collars glabrous, without tufts of hair at the sides; ligules 0.5-2.5 mm, glabrous, obtuse; blades 15-45 cm long, 0.2-0.6 mm wide, convolute, stiff, scabridulous. |
glabrous or hairy, sometimes mostly glabrous, sometimes the distal margins ciliate, varying within a plant; collars with tufts of hair at the sides, hairs 0.5-0.8 mm; ligules 0.3-1.2 mm, glabrous, truncate to rounded; blades 10-20 cm long, 0.8-3.5 mm wide, flat to convolute, abaxial surfaces glabrous or sparsely pilose. |
Panicles | 8-25 cm, open, lax, sparse; branches 2-6 cm, with 1-8 spikelets; pedicels 3-12 mm. |
18-60 cm, open; branches 3-9 cm, spreading, flexuous, often pilose at the axils, with 2-6 spikelets; pedicels 3-10 mm. |
Glumes | subequal, 4-10 mm long, 0.9-1.2 mm wide, narrowly lanceolate, scabridulous, apices aristate; florets 1.5-2.5 mm long, 0.7-0.9 mm wide, terete, widest near the top; calluses 0.1-0.3 mm, acute, strigose, hairs reaching to midlength on the lemmas; lemmas strongly tuberculate, particularly distally, mostly glabrous, narrowing abruptly to the crown, midveins pubescent proximally; crowns about 0.5 mm long, about 0.2 mm wide, straight-sided, rims entire or irregularly lacerate, glabrous; awns 15-35 mm, eccentric, straight to twice-geniculate; anthers 3, 1-1.5 mm. |
subequal, 12-20 mm long, 1.1-2.2 mm wide, narrowly lanceolate, glabrous; florets 7.5-11.5 mm long, about 1.2 mm thick, terete; calluses 1.8-3.5 mm, sharp, strigose; lemmas papillose, evenly pubescent at maturity, constricted below the crown; crowns 0.6-1.1 mm long, 0.5-0.7 mm wide, straight-sided to slightly flared, rims with 0.8-0.9 mm hairs; awns 38-100 mm long, 0.3-0.45 mm thick at the base, strongly twice-geniculate, terminal segment straight; anthers 3.5-5.5 mm, penicillate. |
Caryopses | about 1.2 mm, oblong, dark brown. |
4.5-6 mm. |
2n | = 36. |
= 64. |
Nassella trichotoma |
Nassella pulchra |
|
Distribution |
IL; KY; NC; SC |
CA
|
Discussion | Nassella trichotoma is a native of South America, and has been accidentally introduced into the United States. Because it is on the U.S. Department of Agriculture's noxious weed list, all known populations have been eliminated. New populations should be reported to the Department. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Nassella pulchra grows in oak chaparral and grassland communities of the coast ranges and Sierra foothills of California, extending south into Mexico. It probably never formed extensive grasslands (Hamilton 1997), flourishing primarily in moderately disturbed areas. It resembles N. manicata, but has longer florets and less strongly developed crowns. Nassella pulchra and N. cernua sometimes hybridize. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 177. | FNA vol. 24, p. 174. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Stipeae > Nassella | Poaceae > subfam. Pooideae > tribe Stipeae > Nassella |
Sibling taxa | ||
Synonyms | Stipa pulchra | |
Name authority | (Nees) Hack, ex Arechav. | (Hitchc.) Barkworth |
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