New York Agricultural Experiment Station. 477 



During the first week of June the bushes were sprayed again 

 with the same solution of whale-oil soap, with the effect that they 

 were practically freed from the insects. 



Had the first solution been stronger, two applications would 

 probably have been sufficient. Two rows were left unsprayed 

 with the result shown at Plate XXV. At the time the photo- 

 graph was taken, in early June, but few leaves were left on the 

 bushes as a result of the work of the lice. The treated rows 

 showed much less injury from the insects. 



The plum trees were not sprayed until June 4. They were 

 badly infested at this time, and the young leaves were so badly 

 curled as to make it very difficult to reach all of the lice. The 

 whale-oil soap solution, 1 pound to 7 gallons of water, was used 

 on all of the trees. The effects of this treatment were at once 

 apparent. Practically all the lice were killed on the leaves which 

 were not so badly curled as to prevent the spray from reaching 

 the insects. 



Before the trees were sprayed a second time, about a week 

 later, some of the worst infested trees were trimmed. The tips 

 of the branches having the most curled leaves were cut off. This 

 removed large numbers of lice and left but little refuge for those 

 that remained. The trees were again sprayed with the whale-oil 

 soap solution, as in the first instance, immediately after being 

 trimmed, with the result that, in a short time, but comparatively 

 few live lice could be found. 



Recommendations. 



Do not wait for the leaves to become curled, but spray thor- 

 oughly as soon as the first few lice are observed. Much depends 

 upon the thoroughness of the first application. 



Direct the spray from below so as to drench the under surface 

 of the leaves. 



Use a solution of good whale-oil soap, not weaker than 1 pound 

 to 7 gallons of water. 



When the spraying has been neglected until the leaves have 

 become badly curled, trim oft' the curled tips and spray at once 

 with the whale-oil soap solution, This applies especially to fruit 

 trees. 



