Panicum paludosum
Plants perennial; more or less cespitose, rhizomatous or stoloniferous, free-floating or rooting in shallow water. Culms 30-150 cm tall, 3-7 mm thick, compressed, spongy, glabrous, decumbent and rooting at the lower nodes in shallow water; nodes glabrous; internodes glabrous, smooth. Sheaths usually shorter than the internodes, not keeled, glabrous or sparsely hispid distally; ligules 1-4 mm; blades 10-40 cm long, 5-15 mm wide, flat, glabrous, contracted basally, attenuate distally, apices acute. Panicles 10-25 cm long, 5-17 cm wide, shortly exserted or included basally; primary branches 4-12 cm, ascending to spreading, secondary and higher order branches confined to the distal 2/3, pedicels 1-4 mm, sharply 3-angled, ascending to appressed. Spikelets 3-4 mm long, 0.8-2 mm wide, lanceolate. Lower glumes 0.5-0.9 mm, 1/5 – 1/3 as long as the spikelets, rounded, glabrous, truncate, weakly 1-3-veined; upper glumes and lemmas subequal, glabrous, 9-11-veined, veins prominent, apices acute to accuminate; lower paleas about 2/3 as long as the lower lemmas; lower florets sterile; upper florets 2-2.7 mm, narrowly ellipsoid, smooth, shiny, yellowish. 2n = 54.
Discussion
Panicum paludosum is an Asian species that grows in shallow water. It has been found in Baltimore, Maryland, but may not be established there.
Selected References
None.