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



cm long; spikelets 4 to 4.3 mm long, sparsely papillose-pubescent. 

 Autumnal phase more or less spreading, branching from the middle 



Figure 1436.— Distribution of 

 Panicum oligosanthes. 



Figure 1437.— Panicum ravenelii. Two views of spikelet, and 

 floret, X 10. (Type.) 



and upper nodes, the short branches crowded at the summit. % — 

 Sandy or gravelly woods or open ground, Delaware to Missouri, south 

 to Florida and Texas (fig. 1438). 



95. Panicum leibergii (Vasey) Scribn. (Fig. 1439.) Vernal culms 

 slender, 25 to 75 cm tall, erect from a more or less geniculate base, 

 pilose or scabrous; sheaths papillose-hispid 

 with spreading hairs; ligule obsolete or nearly 

 so; blades ascending or erect, rather thin, 6 to 

 15 cm long, 7 to 15 mm wide, papillose-hispid 

 on both surfaces, often sparsely so above; 

 panicle 8 to 15 cm long, less than half as wide; 

 spikelets 3.7 to 4 mm long, strongly papil- 

 lose-hispid. Autumnal phase leaning, sparingly 

 brandling from the middle and lower nodes. 

 % — Prairies, New York to Manitoba and North Dakota, south to 

 Indiana and Kansas (fig. 1440). 



96. Panicum xanthophysum A. Gray. (Fig. 1441.) Vernal phase 



Figure 1438.— Distribution of 

 Panicum ravenelii. 



Figure 1439.— Panicum leibergii. Two views of spikelet, and floret, X 10. (Type.) 



yellowish green; culms 20 to 55 cm tall, more or less scabrous; sheaths 

 sparsely papillose-pilose; blades erect or nearly so, rather thin, prom- 

 inently nerved, 10 to 15 cm long, 1 to 2 cm wide, glabrous except 

 the ciliate base; panicle 5 to 12 cm long, very narrow, few-flowered, 



