CLIMATE AND PLANT GROWTH. 



47 



1526 



1132 



665 



600 

 '0 



354 



Oak - Brush Type A spen - Fir Spruce - Fir 



Wheat Including Heads\ Water Used 



Wheat Without Heads ] Per Plant 



Water Requirement without heads expressed in 



percent of water requirement with heads 



" Te.mper3tu.re, above. 4-0 f. 



FIG. 25. Water requirement of wheat based on weight of plant including heads, compared 

 with water requirement based on weight, without heads, (Experimental Series No, 2.) 



