HOW TO KNOW THE GRASSES 



37a. Upper leaf sheaths bristly hairy with spreading hairs; leaf blades 

 6—12 mm. wide. Fig. 319. 



Panicum scribnerianuzn Nash 



Perennial; tufted; plants 20 — 50 cm. tall, 

 rather stiff; sheaths sparsely covered with 

 stiff spreading bristles or nearly smooth. The 

 terminal panicles, produced in May and June, 

 are 4 — 8 cm. long and about as broad, pyra- 

 mid-shaped. After the terminal panicles have 

 shed their spikelets, the plants become bushy- 

 branched and produce small, simple panicles 

 partially concealed by the tufted upper leaves. 

 Prairies and open woods, often on dry sandy 

 soil. 



Figure 319 



37b. Upper sheaths glabrous or softly hairy; larger leaf blades 1.5 — 4 

 cm. wide. Fig. 320. 



Panicum latifolium L. 



Perennial; tufted; 45 — 100 cm. tall; terminal 

 panicles produced in June, about 10 cm. long 

 and nearly as wide, with stiff spreading 

 branches; spikelets hairy, 3.4 — 3.7 mm. long. 

 This is one of the most easily recognized of 

 all grasses. The very broad leaf blades are 

 heart-shaped at the base. Roadsides, woods, 

 stream banks. The following species are also 

 wide-leaved. 



Panicum clandestinum L. has very bristly 

 sheaths on the secondary branches. Spike- 

 lets 2.7 — 3 mm. long. 



Panicum boscii Poir. has spikelets over 4 

 mm. long. The nodes of the stems are beard- 

 ed with soft hairs, and the foHage is some- 

 times hairy. 



Figure 320 



38a. Culms glabrous 39 



38b. Culms covered with short fuzz and sometimes with longer hairs . . 40 



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