Nassella trichotoma |
Nassella chilensis |
|
---|---|---|
serrated tussock, serrated tussockgrass, yass tussockgrass |
Chilean needlegrass, Chilean tussockgrass |
|
Habit | Plants perennial; cespitose, not rhizomatous. | Plants perennial; shortly rhizomatous, appearing cespitose, rhizomes slender, somewhat woody. |
Culms | 20-60 cm tall, about 1 mm thick, erect, internodes glabrous; nodes 2-4, pubescent. |
30-100 cm tall, 0.4-0.7 mm thick, bases somewhat bulblike, erect, geniculate and often branching intra-vaginally at the lower cauline nodes, internodes glabrous; nodes 5-8+, glabrous. |
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. |
mostly glabrous, throats sometimes ciliate; collars sparsely hairy, with tufts of hair at the sides, hairs 0.5-1.3 mm; ligules 0.2-0.3 mm, truncate, usually ciliate; blades 3-10 cm long, 1-1.5 mm wide, strongly convolute, stiff, abaxial surfaces glabrous, adaxial surfaces with coarse hairs. |
Panicles | 8-25 cm, open, lax, sparse; branches 2-6 cm, with 1-8 spikelets; pedicels 3-12 mm. |
2-20 cm; branches 0.4-1.2 cm, with 1-4 spikelets; pedicels 0.5-4 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, 3-4.5 mm long, 1.1-1.6 mm wide, ovate, 3-veined, glabrous or puberulent, acuminate; florets 1.6-2.2 mm long, 0.6-0.9 mm wide, obovate to oblong, terete, widest near the top; calluses 0.2-0.3 mm, obtuse, glabrous; lemmas glabrous, smooth, lustrous, transition to the crown not evident; crowns about 0.1 mm long and wide, not differing in texture from the lemmas; awns 7-10 mm, eccentric, rapidly deciduous; anthers about 1 mm or 0.3-0.4 mm, florets with longer anthers presumably chasmogamous, those with shorter anthers presumably cleistogamous. |
Caryopses | about 1.2 mm, oblong, dark brown. |
about 1 mm. |
2n | = 36. |
= 42. |
Nassella trichotoma |
Nassella chilensis |
|
Distribution |
IL; KY; NC; SC |
OR |
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 chilensis is an Andean species that was once collected from a ballast dump in Portland, Oregon. It is not established in the Flora region. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 177. | FNA vol. 24, p. 177. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Stipeae > Nassella | Poaceae > subfam. Pooideae > tribe Stipeae > Nassella |
Sibling taxa | ||
Name authority | (Nees) Hack, ex Arechav. | (Trin.) E. Desv. |
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