GENERA OF GRASSES OF THE UNITED STATES, 231 
Panicum virgatum L. (fig. 189) switch-grass, an erect perennial 3 to 
5 feet tall, with open spreading panicle, is common in the eastern half 
Fic, 139.—Switch-grass, Panicum virgatum. Plant, * 4; two views of spikelet and 
fertile floret, K 10. 
of the United States. It is a constituent of prairie hay. Panicum 
bulbosum UH. B. K., of the Southwest develops well-marked corms 
