HOW TO KNOW THE GRASSES 



40a. Spikelets 2.2 — 2.7 mm. long; leaf sheaths glabrous; culm inter- 

 nodes covered with short, bent hairs. Fig. 323. 



Panicum ashei Pearson 



Perennial; tufted; plants stiffly erect, 25 — 

 50 cm. tall. The pyramid-shaped primary 

 panicles are 5^8 cm. long and have rather 

 few spikelets. The internodes of the culms 

 and portions of the leaf blades tend to 

 be purple. The plants become rather spar- 

 ingly branched, with elongated branches. 

 Dry rocky woods, brushland, often on 

 sandy ground. Primary panicles produced 

 from May to July. 



Figure 323 



40b. Spikelets 1.5 — 1.9 mm. long; leaf sheaths hairy; at least some of 

 the sheaths and internodes covered with a mixture of long hairs 

 and short, fine fuzz. Fig. 324. 



Panicum coluznbianum Scribn. 



Figure 324 



Perennial; tufted; plant 15 — 50 cm. tall; leaf 

 blades 3 — 6 cm. long, 3 — 5 mm. wide, the 

 upper surface glabrous and the lower with 

 fine, short hairs; primary panicles ovoid, 2 — 7 

 cm. long, produced in June and July. Later 

 the plants become much-branched and bushy, 

 often making mats on the ground. Dry sandy 

 or rocky sterile ground, in the open or in 

 thin woods. 



Panicum meridionale Ashe. Plants small 

 and delicate; leaf blades 1.5 — 3 cm. long, 2 — 4 

 mm. wide; upper surfaces of leaves bearing 

 long, erect hairs; spikelets 1.3 — 1.5 mm. long. 

 Sterile soil; N. S. to Minn., Ga., and Ala. 



41a. Spikelets glabrous or hairy, never warty. 



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