Plate LI. Fig. i.—A branch from a Yellow Bellflower tree in full bloom on April io, 
1913, showing the effect of spraying with a solution of nitrate of soda 
plus caustic soda on February 3 previous. 
Fig. 2.—A branch from an unsprayed check tree for comparison with 
figure 1. 
The illustrations are from photographs taken on the same day. 
