46 BULLETIN" 700, U. S. DEPARTMENT OF AGRICULTURE. 



/e 



/7 



/6 



f4 



/.3 



N 



\ 



\ 



\ 



\ 



\ 



\ 



99/ 



^cy* Brush Aspen Spruce r~ir 



Aspen 



Temperature above ^o" 



— Wafer tfepui rem ent~ without heads expressed 



in percent of wafer requirement with hearts 



Wheat w/th Heads \ WcLfer used per pi ant 



Wheat without heads J r r 



Fig. 24.— Water requirement of wheat based on weight of plant including heads, compared 

 with water requirement based on weight without heads. (Experimental Series No. 1.) 



