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MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



phase erect or leaning, producing 

 short densely fascicled branches at 

 the middle and upper nodes, these 

 tufts scarcely as long as the primary 

 internodes. % — Marshes and 

 swampy woods, Coastal Plain, south- 

 ern New Jersey to Florida and 

 Louisiana; Cuba. 



Figure 947. — Panicum lucidum. Two views of spike- 

 let, and floret, X 10. (Type.) 



38. Panicum lucidum Ashe. (Fig. 

 947.) Vernal phase at first erect and 

 resembling that of P. dichotomum, 

 but the weak culms soon decumbent; 

 blades thin, shining, bright green, 

 glabrous, at first erect but soon 

 widely spreading, 4 to 6 mm. wide; 

 panicle resembling that of P. di- 

 chotomum but fewer-flowered; spike- 

 lets 2 to 2.1 mm. long, elliptic, gla- 

 brous (rarely pubescent), the tip of 

 the fruit exposed at maturity. Au- 

 tumnal phase repeatedly branching, 

 forming large clumps or mats of slen- 

 der weak vinelike culms, the branches 

 elongate and diverging at a wide 

 angle, not fascicled, the blades waxy, 

 flat, spreading. % — Wet woods 

 and sphagnum swamps, Coastal Plain, 

 Massachusetts to Florida, Arkansas, 

 and Texas; Indiana (near Lake 

 Michigan), Michigan (Port Huron). 

 P. lucidum var. opacum Fernald. 

 Blades not glossy. Virginia. 



39. Panicum sphagnicola Nash. 

 (Fig. 948.) Vernal phase gra}dsh olive 

 green; culms strongly flattened, erect 

 or reclining, 50 to 100 cm. tall; 

 sheaths soon divaricate; blades gla- 

 brous, 3 to 7 mm. wide; panicle 

 narrow, 5 to 6 cm. long; spikelets 2.5 

 mm. long, elliptic, glabrous or mi- 

 nutely pubescent toward the summit. 

 Autumnal phase decumbent or finally 

 prostrate-spreading, divaricately 



branching from all the nodes, the 

 branches slender, elongate. % 

 Edges of cypress swamps, in sphag- 

 num bogs, and in similar moist shady 

 places, southern Georgia and Florida. 



7. Spreta. — Culms tufted, rather 

 stiff, mostly glabrous or nearl} r 

 so; ligules densely hairy, 2 to 5 

 mm. long; blades mostly firm; 

 spikelets 5- to 7-nerved, mostly 

 pubescent. Autumnal culms with 

 rather short-tufted branchlets 

 and greatty reduced leaves and 

 panicles. 



Figure 948. — Panicum sphagnicola. Two views of 

 spikelet. and floret, X 10. (Type.) 



Figure 949. — Panicum spretum. Two views of spike- 

 let, and floret, X 10. (Type.) 



40. Panicum spretum Schult. (Fig. 

 949.) Vernal culms 30 to 90 cm. tall, 

 erect; sheaths glabrous; ligule 2 to 3 

 mm. long; blades firm, ascending to 

 re flexed, 4 to 8 mm. wide, sparingly 

 ciliate around the base; panicle 8 to 

 12 cm. long, the branches ascending 

 or appressed; spikelets about 1.5 mm. 

 long, elliptic, rarely glabrous. Au- 

 tumnal phase mostly reclining, the 

 early branches elongate, the subse- 

 quent branches in short fascicles. % 

 — Wet usually sandy soil, Coastal 

 Plain, Nova Scotia to Florida and 

 Texas; Indiana and Michigan. 



41. Panicum lindheimeri Nash. 

 (Fig. 950.) Vernal culms ascending 

 or spreading, 30 to 100 cm. tall, the 

 lower internodes and sheaths some- 



