Bui. 453, U. S. Dept. of Agriculture. 



Plate I. 



iJ\: '■■: 



Fig. 1.— Norway-Pine Seed Bed, 1 Year Old, Halsey, Nebr. 



Plat in center untreated Remainder of bed treated at time of sowing with a solution containing 

 three-sixteenths fluid ounce of sulphuric acid per square foot of bed. Practically all of the seedlings 

 in the untreated plat have been destroyed by damping-ofL Photographed by Charles B. Pool 

 (PI). 



Fig. 2.— Western Yellow-Pine Seed Bed, Kansas Sandhills. 



Foreground untreated. Background treated at time of sowing with a sulphuric-acid solution. Most 

 of the seedlings in the untreated plat have been destroyed by damping-off. Photographed by Dr, 

 J. V. Hofmann (F 2). 



