HOW TO KNOW THE GRASSES 



51a. Plants producing rhizomes; spikelets scythe-shaped, set at an 

 angle to the pedicel. Fig. 336. 



Panicum anceps Michx. 



Perennial; short scaly rhizomes present; 

 culms erect, 50 — 100 cm. tall; leaves smooth 

 or hairy, elongated, 4 — 12 mm. wide; pani- 

 cles open, 15—40 cm. long; spikelets 3.4 — 

 3.8 mm. long, curved. Open moist ground 

 and woods, especially on sandy soil. July 

 — September. 



Panicum rhizomatum H. & C. is similar 

 but has more elongated rhizomes, contract- 

 ed panicles, and spikelets 2.4 — 2.8 mm. 

 long. Sandy soil on the Atlantic and Gulf 

 Coastal Plains, Maryland to Texas; Ten- 

 nessee. 



Figure 336 



51b. Plants without rhizomes; spikelets straight or nearly so, set in 

 line with the pedicel. Fig. 337. 



Panicum agrostoides Spreng. 



«// 



Perennial; tufted; culms 50 — 100 cm. tall- 

 panicles elliptical, the branches densely clus- 

 tered with nearly sessile spikelets; spikelets 

 green or somewhat reddish, 1.8 — 2.2 mm. 

 long. Moist shores and meadows, swamps, 

 alluvial mud flats. July — September. 



Panicum condensum Nash is similar but has 

 a denser panicle; spikelets 2.2 — 2.5 mm. long. 

 Wet ground on the Coastal Plains, Pennsyl- 

 vania to Florida and Texas. 



Figure 337 



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