MANUAL OF THE GRASSES OF THE UNITED STATES 



times ascending-pubescent; ligule 4 

 to 5 mm. long; blades 6 to 8 mm. wide, 

 glabrous; panicle 4 to 7 cm. long, 

 about as wide; spikelets 1.4 to 1.6 

 mm. long, obovate. Autumnal phase 

 usually stiffly spreading or radiate- 

 prostrate, with elongate internodes 

 and tufts of short appressed branches ; 

 blades involute-pointed, often con- 

 spicuously ciliate at base. % — 

 Dry sandy or sterile woods or open 

 ground, Quebec and Maine to Minne- 

 sota, south to northern Florida and 

 New Mexico; California. 



655 



Figure 950. — Panicum lindheimeri. Plant, X 1; two 

 views of spikelet, and floret, X 10. (Chase 4449, 

 Miss.) 



42. Panicum leucothrix Nash. (Fig. 

 951.) Vernal phase light olive green; 

 culms 25 to 45 cm. tall, erect or as- 

 cending, appressed papillose-pilose, 

 the nodes pubescent; sheaths papil- 

 lose-pilose; ligule 3 mm. long; blades 

 3 to 7 mm. wide, glabrous or sparsely 

 villous on the upper surface, velvety- 

 puberulent beneath; panicle 3 to 8 

 cm. long, rather densely flowered; 

 spikelets 1.2 to 1.3 mm. long, densely 

 papillose-pubescent. Autumnal culms 

 at first sending out from lower and 



Figure 951. — Panicum leucothrix. Two views of spike- 

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



middle nodes long branches similar 

 to primary culms, later producing 

 more or less fascicled branches. % 

 — Low pinelands, Coastal Plain, New 

 Jersey to Florida and Texas; Tennes- 

 see; West Indies; Colombia. 



43. Panicum longiligulatum Nash. 

 (Fig. 952.) Vernal culms 30 to 70 

 cm. tall; sheaths glabrous; ligule 2 

 to 3 mm. long; blades 4 to 8 mm. 

 wide, glabrous on the upper surface, 

 puberulent beneath; panicle 3 to 8 

 cm. long, the slender branches stiffly 

 ascending; spikelets 1.1 to 1.2 mm. 

 long. Autumnal culms reclining, the 

 branches spreading, the branchlets 

 crowded, the blades subinvolute. % 

 — Low pine barrens and swamps, 

 Coastal Plain, Pennsylvania (Bucks 

 County), Delaware to Florida and 

 Texas; Tennessee; Central America. 



Figure 952. — Panicum longiligulatum. Two views of 

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



44. Panicum wrightianum Scribn. 

 (Fig. 953.) Vernal culms weak, slen- 

 der, ascending from a decumbent 

 base, 15 to 60 cm. tall, minutely 

 puberulent; sheaths glabrous or pu- 

 berulent; ligule 2 to 3 mm. long; 

 blades 2 to 4 cm. long, 3 to 5 mm. 

 wide, glabrous or puberulent beneath 

 and minutely pilose above; panicle 

 3 to 6 cm. long; spikelets 1 mm. 

 long. Autumnal culms decumbent- 

 spreading, sending out from lower 

 and middle nodes numerous ascend- 

 ing branches, becoming bushy- 

 branched, the flat or subinvolute 



