DESCRIPTIVE MANUAL 



GRAMINEAE, GRASS FAMILY. 

 This large family is of great economic importance, since it con- 

 tains many of our food plants, including the well known cereals, 



Fig. 2. Johnson Grass (Sorghum halepense) ; a, sessile splkelets. A most trou- 



blesoume weed. 

 (Lamson-Scribner, U. S. Dept. Agr.) 



Fig. 2-A. Distribution of Johnson Grass. Reported recently from southwestern 



Iowa. 



