50 
This orchard, which had been practically abandoned, had just been bought for 
planting to apples. It was chosen as offering most adverse conditions for the produc- 
tion of good fruit and a most severe test of the efficacy of the treatments used. 
Plats 9-15. — Vigorous, well-grown, well-kept, 8-year-old Elberta trees. Orchard 
elevated and slightly rolling, with excellent air and surface drainage. Sandy clay 
soil. Had received a winter application of lime-sulphur. Well pruned, cultivated, 
and fertilized. Crop good. 
Plats 16-22. — Vigorous, 8-year-old Belle trees, well kept, but slightly under size. 
Sandy clay soil. Orchard elevated and slightly rolling, with good air and surface 
drainage. Had received the winter application of lime-sulphur. Well pruned, cul- 
tivated, and fertilized. Crop good. 
RESULTS ON FOLIAGE. 
Observations made at frequent intervals throughout the season 
showed no evidence of spray injury upon any of the plats treated 
with self -boiled lime-sulphur. In plats 9, 9A, 9B, and 11, however, 
sprayed with the sulphur paste and arsenate of lead, a considerable 
amount of " shot-holing" and yellowing of the foliage began to appear 
about the middle of July. This was followed by some defoliation 
throughout late July and early August. The fruit of these plats was 
very highly colored but not injured. The foliage of the parallel 
self -boiled lime-sulphur plats (12, 13, and 14) was not injured, being 
quite vigorous, well colored, and free from disease except for a limited 
amount of leaf injury which possessed the typical characteristics of 
peach bacteriosis (Bacterium pruni Smith). The foliage of the con- 
trol plat, though less vigorous than that of plats 12, 13, and 14 and 
not so well colored, showed very little yellowing and defoliation. 
These facts strongly suggested that the trouble in plats 9, 9A, 9B, 
and 11 was some type of spray injury. 
Inasmuch as each of the earlier treatments had been omitted from 
one or another of plats 9 to 15, conclusive data appear to be available. 
The key to the situation seems to he in plat 10, which was treated 
in the same manner as the adjacent plats, 9 and 9A, except that the 
second application was omitted. On this plat, directly adjacent to 
plat 9, the foliage went through the season hi excellent condition, 
closely approaching that of the self-boiled lime-sulphur plats in vigor 
and color. Thus, all plats (9, 9A, 9B, and 11) which received the 
sulphur paste and arsenate of lead in the second application were 
generally affected, while none of the remaining plats showed any 
evidence of spray injury. Therefore, it seems conclusive that the 
injury must have resulted from this treatment. 
No experiments were made to test separately and comparatively 
the action of the sulphur paste and of arsenate of lead. However, 
since sulphur alone has proved to be one of the safest fungicides 
known and since the sulphur paste caused no injury when applied 
alone in the third treatment on plat 10, it seems evident that the 
