PRELIMINARY OBSERVATIONS. 



Weather conditions, Washington, D. C., June 20 to July 15, 1902. 



In the morning, before the trees were sprayed. 

 OBSERVATIONS. 



The trees were first sprayed on June 20. The next day a heavy 

 rain fell, which seemed to wash off the Paris Green completely. After 

 waiting for 10 days i. e., until July 1 to see whether the trees 

 would be affected, they were again sprayed, no damage being observed 

 at that time. After the second spraying observations were made on 

 the following dates: July 5, 10, 16, August 11, and September 18, 1902. 



With the peaches the results were somewhat irregular on account of 

 the varying hardiness of 4he trees and the fact that some of them were 

 attacked later in the season by insect pests; but a few general conclu- 

 sions can be drawn. As one would expect from previous experiments, 

 the peaches did not show any injury from the spray until after the first 

 considerable rain, on July 10. Then the trees on which lime was not 

 used were all more or less burned and partly defoliated, except the one 

 sprayed with solution No. 3 (6 per cent of arsenious oxid). This tree 

 was very hardy and was not injured in any way. The tree sprayed 

 with solution No. 1 (4.29 per cent of arsenious oxid). without lime, was 



