Panicum repens |
Panicum hemitomon |
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couch panicum, creeping panic, panic rampant, torpedo grass, wainaku grass |
maidencane, mountain panic |
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Habit | Plants perennial; rhizomatous, forming extensive colonies, rhizomes long, to 5 mm thick, branching, scaly, sharply pointed. | Plants perennial; robust, aquatic or semi-aquatic, forming extensive colonies through spreading rhizomes. |
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. |
50-200 cm, mostly erect and sterile, glabrous, often rooting from the lower nodes if submerged. |
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. |
usually glabrous, or pilose or hirsute at the lowermost sheath, especially distally; ligules shorter than 1 mm; blades 8-35 cm long, 5-15 mm wide, ascending or spreading, abaxial surfaces glabrous, adaxial surfaces usually scabridulous or pubescent, bases slightly narrowed, margins scabrous, apices long-tapering. |
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. |
10-30 cm long, less than 1 cm wide; branches mostly short, appressed-ascending, with fascicles of congested spikelets; ultimate branchlets 1-sided; pedicels 0.2-1.8 mm. |
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. |
2-2.8 mm, subsessile, lanceoloid, slightly laterally compressed, glabrous, acute. |
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 1/2 as long as the spikelets, slightly keeled along the midveins, 3-veined, acute; upper glumes and lower lemmas similar, glumes slightly shorter than the lemmas, faintly keeled on the back, acute; lower florets staminate; lower paleas subequal to the lower lemmas; upper florets 2-2.5 mm, 2/5 to almost as long as the spikelets, narrowly ellipsoid; upper lemmas relatively thin, flexible, pale, acuminate, clasping the paleas only at the base. |
2n | - 36, 40, 45, 54. |
= 36, 40. |
Panicum repens |
Panicum hemitomon |
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Distribution |
AL; CA; FL; GA; LA; MS; NC; SC; TX; HI
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AL; DE; FL; GA; LA; MD; MS; NC; NJ; SC; TN; TX; VA
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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 hemitomon forms extensive, nearly pure stands in water or wet soils such as marshes, swamps, and along the shores of streams, canals, ditches, lakes, and ponds. It is restricted to the United States. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 25. | FNA vol. 25, p. 484. |
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Repentia | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Phanopyrum > sect. Hemitonia |
Sibling taxa | ||
Name authority | L. | Schult. |
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