MANUAL OF THE GRASSES OF THE UNITED STATES 



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31. Panicum dichotomum L. (Fig. 1322.) Vernal phase often 

 purplish; culms erect from a knotted crown, 30 to 50 cm tall, the lower 

 nodes sometimes with a few spreading hairs; blades spreading, 4 to 8 

 mm wide, glabrous; panicle 4 to 9 cm long, the axis and spreading 

 branches flexuous ; spikelets 2 mm long, elliptic, glabrous (rarely pu- 

 bescent) ; second glume shorter than the fruit at maturity. Autumnal 

 phase much branched at the middle nodes, the lower part usually 

 erect and devoid of blades, giving the plants the appearance of dimin- 

 utive trees; blades numerous, often involute. % — Dry or sterile 



Figure 1323.— Distribution of 

 Panicum dichotomum. 



Figure 1324.— Panicum barbu- 

 latum. Two views of spike- 

 let, and floret, X 10. (Type.) 



Figure 1325.— Distribution of 

 Panicum barbulatum. 



woods, New Brunswick to Illinois, south to Florida and eastern 

 Texas (fig. 1323). 



32. Panicum barbulatum Michx. (Fig. 1324.) Vernal phase, 

 resembling that of P. dichotomum, the culms 50 to 80 cm tall, the lower 

 nodes usually bearded; blades slightly wider, panicle slightly larger, 

 spikelets 2 mm long, glabrous; second glume as long as the fruit at 

 maturity. Autumnal phase diffusely branched, forming very large 

 topheavy reclining bunches, the slender branches recurved, the 

 numerous flat blades horizontally spreading. % —Sterile or rocky 

 woods, Massachusetts to Michigan and Missouri, south to Georgia 

 and eastern Texas (fig. 1325). This species seems to intergrade with 



Figure 1326. — Panicum yadkinense. 

 Two views of spikelet, and floret, 

 X 10. (Type coll.) 



Figure 1327.— Distribution of 

 Panicum yadkinense. 



P. dichotomum, but typically the autumnal phases are distinctly differ- 

 ent. The vernal culms of P. barbulatum are usually more robust and 

 the lower nodes are rather strongly bearded. 



33. Panicum yadkinense Ashe. (Fig. 1326.) Vernal phase simi- 

 lar to that of P. dichotomum, the culms sometimes 1 m tall; sheaths 

 bearing pale glandular spots; blades longer and 8 to 11 mm wide; 

 panicle 10 to 12 cm long; spikelets 2.3 to 2.5 mm long, elliptic to sub- 

 fusiform, pointed a little beyond the fruit, glabrous. Autumnal phase 

 erect or leaning, loosely branching from the middle nodes, the blades 

 not conspicuously reduced. % — Moist woods and thickets, Penn- 

 sylvania to Illinois, south to Georgia and Louisiana (fig. 1327). 

 Named from Yadkin River, N.C. 



