Panicum dichotomiflorum |
Panicum anceps |
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fall panicgrass, fall panicum, knee grass, panic d'automne, smooth witchgrass |
beak panicgrass |
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Habit | Plants annual or short-lived perennials in the Flora region, perennial in the tropics; usually terrestrial, sometimes aquatic but not floating. | Plants perennial; conspicuously rhizomatous, rhizomes short or elongate, stout, scaly. | ||||||||||||
Culms | 5-200 cm tall, 0.4-3 mm thick, decumbent to erect, commonly geniculate to ascending, rooting at the lower nodes when in water, simple to divergently branched from the lower and middle nodes, usually succulent, slightly compressed, glabrous; nodes usually swollen, sometimes constricted on robust plants, glabrous; internodes glabrous, shiny, pale green to purplish. |
30-130 cm, terete to slightly compressed. |
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Sheaths | compressed, inflated, sparsely pubescent near the base, elsewhere mostly glabrous, sparsely pilose, or hispid, hairs sometimes papillose-based, margins or throat ciliate, with papillose-based hairs; ligules 0.5-2 mm; blades 10-65 cm long, 3-25 mm wide, glabrous or sparsely pilose, often scabrous near the margins, midribs stout, whitish. |
laterally compressed, glabrous or sparsely to densely pilose or villous, especially at the summit; ligules less than 0.5 mm, membranous, erose, often brownish; blades 10-50 cm long, 4-12 mm wide, erect, adaxial surfaces pilose at least basally, glabrous or pilose abaxially. |
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Panicles | 4-40 cm, diffuse, lax, with a few spikelets; branches to 15 cm, alternate or opposite, occasionally verticillate, ascending to spreading, stiff, scabrous; pedicels 1-6 mm, sharply 3-angled, scabrous, expanded to cuplike apices, appressed mostly to the abaxial side of the branches. |
10-40 cm, 1/4 - 2/3 as wide as long, well-exserted at anthesis; branches relatively few, stiffly spreading or ascending; ultimate branchlets 1-sided; pedicels 0.1-3 mm, scabridulous to scabrous, appressed. |
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Spikelets | 1.8-3.8 mm long, 0.7-1.2 mm wide, ellipsoid to narrowly ovoid, light green to red-purple, glabrous, acute to acuminate. |
2.3-3.9 mm, narrowly ellipsoid to ovoid, usually subsessile, usually pale to yellowish-green, glabrous, often falcate and gaping at the apices, rarely lanceolate, densely crowded on short, appressed branchlets, set obliquely on short pedicels. |
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Lower glumes | 0.6-1.2 mm, 1/4 - 1/3 as long as the spikelets, 0-3-veined, obtuse to acute; upper glumes and lower lemmas similar, exceeding the upper florets by 0.3-0.6 mm, 7-9-veined; lower paleas vestigial to almost as long as the lower lemmas; lower florets sterile; upper florets 1.4-2.5 mm long, 0.7-1.1 mm wide, narrowly ellipsoid, smooth, shiny, stramineous to nigrescent, with pale veins. |
A-A as long as the spikelets, 3-veined, keels scabrous, apices acute; upper glumes and lower lemmas subequal, keeled, beaked, usually gaping at the apices; lower florets sterile; lower paleas subequal to the lower lemmas; upper florets 1.5-2.2 mm long, about 1 mm wide, 2/5 – 3/4 as long as the spikelets, apices with a tuft of minute, thick hairs; upper lemmas thick, stiff, clasping the upper paleas throughout their length. |
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2n | = 36, 54. |
= 18, 36. |
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Panicum dichotomiflorum |
Panicum anceps |
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Distribution |
AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; HI; PR; BC; NB; NS; ON; QC
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AL; AR; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MD; MO; MS; NC; NJ; NY; OH; OK; PA; SC; TN; TX; VA; WV
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Discussion | Panicum dichotomiflorum grows in open, often wet, disturbed areas such as cultivated and fallow fields, roadsides, ditches, open stream banks, receding shores, clearings in flood plain woods, and sometimes in shallow water. It is probably native throughout the eastern United States and adjacent Canada, but introduced elsewhere, including in the western United States. Its size and habit may be partly under genetic control, but these features also seem to be strongly affected by moisture levels, soil richness, competition, and the time of germination. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Panicum anceps grows in low, moist, primarily sandy areas, pine savannahs, the borders of flood-plain swamps, mesic woodlands, roadsides, and upland pine-hardwood forests. It is restricted to the United States. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 469. | FNA vol. 25, p. 478. | ||||||||||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Dichotomiflora | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Agrostoidea > sect. Agrostoidea | ||||||||||||
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Subordinate taxa | ||||||||||||||
Name authority | Michx. | Michx. | ||||||||||||
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