Panicum repens |
Panicum urvilleanum |
|
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couch panicum, creeping panic, panic rampant, torpedo grass, wainaku grass |
desert panicgrass, silky panic grass |
|
Habit | Plants perennial; rhizomatous, forming extensive colonies, rhizomes long, to 5 mm thick, branching, scaly, sharply pointed. | Plants perennial. |
Culms | 20-90 cm tall, 1.8-2.8 mm thick, erect, rigid, simple or branching from the lower and middle nodes; nodes glabrous or sparsely hispid; internodes glabrous. |
50-100 cm, erect, solitary or in small tufts from stout, scaly, creeping to vertical rhizomes or stolons, simple or branching at the base; nodes densely villous. |
Sheaths | generally shorter than the internodes, not keeled, lower nodes glabrous or hispid, hairs papillose-based, particularly near the summits; ligules 0.5-1 mm; blades 3-25 cm long, 2-8 mm wide, often distichous, flat to slightly involute, firm, adaxial surfaces pilose basally, glabrous or sparsely pubescent abaxially. |
densely villous; ligules membranous, ciliate, hairs 1.5-2 mm; blades 20-60 cm long, 4-10 mm wide, ascending to spreading, strigose to subglabrous, flat basally, tapering to a long, involute point. |
Panicles | 3-24 cm long, usually less than 5 cm wide, open; primary branches 2-11 cm, alternate, few, stiffly ascending to spreading; pedicels 1-6 mm, subappressed. |
20-30 cm long, 3-9 cm wide, narrow, shortly exserted; branches slender, ascending; secondary branches and pedicels 1-4 mm, crowded, ascending to appressed. |
Spikelets | 2.2-2.8 mm long, 0.8-1.3 mm wide, ellipsoid-ovoid, pale green, acute, upper glumes and lower lemmas sometimes separating (gaping) beyond the florets. |
5-7 mm, densely villous, hairs silvery or tawny-white. |
Lower glumes | 0.5-1 mm, 1/5 – 2/5 as long as the spikelets, glabrous, faintly 1-5-veined, subtruncate to broadly acute; upper glumes and lower lemmas glabrous, extending 0.1-0.5 mm beyond the upper florets, scarcely separated; upper glumes 7-11-veined, shorter than the lower lemmas, acute to short-acuminate; lower florets staminate; lower lemmas 7-11-veined; lower paleas 1.9-2.1 mm, oblong; upper florets 1.8-2.7 mm long, 0.7-1.3 mm wide, broadly ellipsoid, broadest at or above the middle, glabrous, shiny, smooth, apices rounded. |
about 3/4 the length of the spikelets, 7-11-veined; upper glumes and lower lemmas 7-15-veined; lower florets staminate; lower paleas about as long as the lower lemmas; upper florets striate, margins of the upper lemmas villous, hairs white; lodicules very large. |
2n | - 36, 40, 45, 54. |
= 36. |
Panicum repens |
Panicum urvilleanum |
|
Distribution |
AL; CA; FL; GA; LA; MS; NC; SC; TX; HI
|
AZ; CA
|
Discussion | Panicum repens grows on open, moist, sandy beaches and the shores of lakes and ponds, occasionally extending out into or onto the water. It is mostly, but not exclusively, coastal. It grows on tropical and subtropical coasts throughout the world and may have been introduced to the Americas from elsewhere. Small plants having small, dense panicles of purplish spikelets with longer, subacute lower glumes have been named Panicum gouinii E. Fourn., but they intergrade with more typical plants and do not seem to merit taxonomic recognition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Panicum urvilleanum grows on desert sand dunes and in creosote bush scrubland in the Mojave and Colorado desert regions of southern California, southern Nevada, and western Arizona. It also grows in Peru, Chile, and Argentina. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 25. | FNA vol. 25, p. 475. |
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Repentia | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Urvilleana |
Sibling taxa | ||
Name authority | L. | Kunth |
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