178 Andropogoneae Andropogon 



Spikelets in slender, solitary, or digitate racemes which are terminal or lateral 



145. Andropogon, p. 178. 



Spikelets in terminal panicles only. 



Pedicellate spikelets present; culms solid 147. Sorghum, p. 180. 



Pedicellate spikelets lacking (only the hairy pedicel present); culms hollow 



148. SORGHASTRUM, p. 181. 



143-112. ERIANTHUS Michx. 



1. Erianthus alopecuroides (L.) Ell. {Erianthus diva r teat us (L.) 

 Hitchc. of Gray, Man., ed. 7, Britton and Brown, lllus. Flora, ed. 2, and 

 Deam, Grasses of Ind.) Silver Plumegrass. This species is known as a 

 native only in Perry County where I found it on a wooded slope along the 

 Ohio River about 5 miles east of Cannelton. It was also noted in a fallow 

 field in the same county. 



Southern N. J., s. Ind., s. Mo., and Okla., southw. to Fla. and Tex. 



Erianthus Ravennae (L.) Beauv. Ravenna or Plume Grass. This 

 species is a native of southern Europe and is often cultivated. There is no 

 record of its escape. It is easily distinguished from the preceding species 

 by having three stamens and by its scabrous sheaths. 



Miscanthus sinensis Anders. Eulalia. This grass is a native of China 

 and is often cultivated. There is no record of its escape. It is easily dis- 

 tinguished from Erianthus by the fan-shaped panicle and by the continuous 

 rachis of the racemes. 



145-134. ANDROPOGON L. 



Branches of inflorescence ending in a single raceme 1. A. scoparius. 



Branches of inflorescence ending in a pair or fascicle of racemes. 



Racemes of each branchlet generally 3-7, 5-13 cm long; sessile spikelets 6.5-10 mm 



long; stamens 3 2. A. furcatus. 



Racemes of each branchlet 2 (rarely 3 or 4), 1.5-4 cm long; sessile spikelets less 

 than 6 mm long; stamens 1. 

 Awns coiled at the base; sessile spikelets generally 4-4.5 mm long, 0.7-0.8 mm wide; 

 peduncles of the primary racemes elongated so that the racemes are borne 



beyond the spathes; spathes inflated, at least at maturity 3. A. Elliottii. 



Awns not coiled at the base; sessile spikelets 3-3.5 mm long, about 0.6 mm wide; 

 none of the peduncles elongated so that the racemes extend beyond the 

 spathes ; spathes not inflated 4. A. virginicus. 



1. Andropogon scoparius Michx. (Schizachyrium scoparium (Michx.) 

 Nash of Britton and Brown, lllus. Flora, ed. 2.) Prairie Beardgrass. 

 BROOMSEDGE. Map 331. This species occurs throughout the state in poor 

 or impoverished soils and moist or dry, sandy soils, and is also rapidly 

 becoming established in the better soils of the Tipton Till Plain. It is 

 found on washed slopes and interdunal flats, in abandoned fields, and along 

 roadsides and railroads. 



The extreme variability of this species has led authors to describe many 

 forms. My Indiana specimens show a wide range of variability, yet I hesi- 

 tate to refer any of my specimens to a variety. For example, about half 

 of my specimens are glabrous, and the other half vary from those with a 

 few hairs on the sheaths to those with a villous pubescence. Andropogon 



