653 



Figure 944. — Panicum yadkinense. Two views of 

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



MANUAL OF THE GRASSES OF THE UNITED STATES 



34. Panicum barbulatum Michx. 

 (Fig. 943.) Vernal phase, resembling 

 that of P. dichotomum, the culms 50 

 to 80 cm. tall, the lower nodes usually 

 bearded ; blades slightly wider, panicle 

 slightly larger, spikelet s 2 mm. long, 

 glabrous; second glume as long as 

 the fruit at maturity. Autumnal 

 phase diffusely branched, forming 

 very large topheavy reclining bunches, 

 the slender branches recurved, the 

 numerous flat blades horizontally 

 spreading. % — Sterile or rocky 

 woods, Massachusetts to Michigan 

 and Missouri, south to Georgia and 

 eastern Texas. This species seems to 

 intergrade with P. dichotomum, but 

 typically the autumnal phases are 

 distinctly different. The vernal culms 

 of P. barbidatum are usually more 

 robust and the lower nodes are rather 

 strongly bearded. 



Figure 945. — Panicum roanokense. Two views of 

 spikelet, and floret, X 10. (Ashe, N. C.) 



at first stiffly erect, later somewhat 

 spreading, 3 to 8 mm. wide, glabrous; 

 panicle 4 to 8 cm. long; spikelets 2 

 mm. long, turgid, elliptic, glabrous, 

 the second glume often purple at 

 base. Autumnal phase erect or de- 

 cumbent, branching at the middle 

 and upper nodes, the branches nu- 

 merous but not in tufts, the reduced 

 blades subinvolute. % — Open 

 swampy woods or wet peaty mead- 

 ows, Coastal Plain, southeastern Dela- 

 ware to Florida and Texas; Jamaica. 



Figure 943. — Panicum barbidatum. Two views of 

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



35. Panicum yadkinense Ashe. 

 (Fig. 944.) Vernal phase similar to 

 that of P. dichotomum, the culms 

 sometimes 1 m. tall; sheaths bearing 

 pale glandular spots; blades longer 

 and 8 to 11 mm. wide; panicle 10 

 to 12 cm. long; spikelets 2.3 to 2.5 

 mm. long, elliptic to subfusiform, 

 pointed a little beyond the fruit, gla- 

 brous. Autumnal phase erect or 

 leaning, loosely branching from the 

 middle nodes, the blades not con- 

 spicuously reduced. % — Moist 

 woods and thickets, Pennsylvania to 

 Michigan and Illinois, south to Geor- 

 gia and Texas. Named from Yadkin 

 River, N.C. 



36. Panicum roanokense Ashe. 

 (Fig. 945.) Vernal phase somewhat 

 glaucous olive green; culms erect or 

 ascending, 50 to 100 cm. tall; blades 



Figure 946. — Panicum caerulescens. Two views of 

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



37. Panicum caerulescens Hack, 

 ex Hitchc. (Fig. 946.) Vernal phase 

 similar to that of P. roanokense; 

 culms more slender; blades ascending 

 or spreading, commonly purplish 

 beneath; panicle 3 to 7 cm. long; 

 spikelets 1.5 to 1.6 mm. long, obo- 

 void, turgid, glabrous. Autumnal 



