Fig. io6. — The North American Prairie: mid- and short-grass communities. 

 A, Nebraska prairie area dominated principally by ' mid ' Grasses, with shrubs 

 and trees in depressions. (By permission from Plant Ecology, by Weaver & 

 Clements, copyright date 1938, McGraw-Hill Book Co.) B, short-grass com- 

 munity in Colorado. (Phot. U.S. Forest Service.) C, area similar to (B), but 

 overgrazed and in poor condition, with bad weeds, including Cacti. (Phot. U.S. 



Forest Service.) 



362 



