No. 20. 



ANDROPOGON SACCHAROIDES Swartz. 



Rootstock short. Roots strong. 



Culms tufted, smooth (nodes bearded or in some forms smooth), simple or 

 branched, erect, 2 to 4 feet high, often with 5 or 6 joints. 



Lower leaves 1 foot or more long; blade flat, narrow, acuminate, somewhat scab- 

 rous on both surfaces and on the margins; sheaths smooth, striate, shorter than 

 the internodes, open; ligules broadly ovate, laciniate. 



Inflorescence paniculate, oblong, about 4 inches long, composed of numerous 

 (20 to 50) closely approximate and appressed sessile spike-like branches 1 inch or 

 more long ; spikelets imbricated. 



Spikelets in pairs at the joints of the branches, one sessile and perfect, the other 

 on a short pedicel and either male or imperfect. Perfect spikelets 2 lines long with 

 2 outer hard glumes and 2 inner hyaline ones; first about 7-nerved, sparsely 

 hairy, 2-toothed at the apex, second obscurely 3-nerved, third and fourth hyaline, 

 latter terminating in a twisted awn sometimes 8 or 10 lines long. Male or sterile 

 spikelet on a pedicel of about its own length, consisting of only 1 linear, pubescent, 

 5- to 7-nerved, glume; pedicel covered with long, fine, white hairs. , 



PLATE XX; a, perfect spikelet; 6, both the sterile and perfect spikelets. 



This species is common on rocky banks and borders of streams. It extends 

 northward to southern Colorado and Kansas, and deserves trial as an agricultural 

 grass for dry and sandy lands. There are several varieties. 



