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



9. Columbiana. — Culms and sheaths appressed-pubescent to crisp- 

 puberulent, the culms stiff; ligules mostly less than 1 mm long 

 (sometimes to 1.5 mm in P. tsugetorum and P. oricola); blades 

 firm, thick, stiffly ascending; spikelets 5- to 9-nerved, pubescent, 

 the first glume mostly one-third to half as long as the spikelet. 

 Autumnal culms freely branching, the branches and stiff blades 

 mostly appressed. 

 62. Panicum malacon Nash. (Fig. 1381.) Vernal culms erect to 



stiffly spreading, purplish olive-green; culms and sheaths appressed- 



FlGURE 1379.— Distribution of 

 Panicum scoparioides. 



Figure 1380.— Panicum shastense. 

 Two views of spikelet, and floret, 

 X 10. (Type.) 



pubescent, the culms 30 to 50 cm tall; blades 3 to 5 mm wide, sharply 

 acuminate, puberulent beneath, puberulent to glabrous above; 

 panicle 4 to 7 cm long, the branches few, stiffly ascending, the pedicels 

 long and stiff; spikelets 3 to 3.2 mm long, obovate, the first glume 

 distant, about half as long as the spikelet. Autumnal culms subde- 

 cumbent-spreading, branching from the lower and middle nodes, the 

 branches appressed. % — Dry pine woods, high pineland, 

 North Carolina (Wilmington) ; Florida. 



63. Panicum deamii Hitchc. and Chase. (Fig. 1382.) Vernal 

 phase yellowish green; culms 25 to 35 cm tall, erect or ascending, 



Figure 1381. — Panicum malacon. Two views 

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



Figure 1382. — Panicum deamii. 

 spikelet, and floret, X 10. 



papillose-pilose; sheaths papillose- villous, densely so at base and 

 summit; blades suberect, 8 to 15 cm long, 4 to 6 mm wide, sparsely 

 villous on the upper surface, appressed-pflose beneath; panicle rather 

 short-exserted, 6 to 10 cm long, the branches ascending; spikelets 2.8 

 to 2.9 mm long, pilose. Autumnal culms branching from the middle 

 and upper nodes, forming a somewhat bushy summit, the culms 

 sprawling. % — Sand dunes, northern Indiana; Iowa. 



64. Panicum commonsianum Ashe. (Fig. 1383.) Vernal phase 

 greenish olive, drying brownish; culms and sheaths appressed-pilose, 



