SOME INSECTS INJURIOUS TO ORCHARD FRUITS 543 



plum, apple and quince are most injured 'n the order named, 

 while cherry and European plum are less injured. 



Control. As yet no spray has been found for use in summer 

 which will more than check the increase of the pest without 

 injury to the tree, and summer spraying is resorted to only when 



FIG. 395. One of the most important native enemies of the San Jose scale, 

 a little black ladybird-beetle (Microweisea misella): a, beetle; b, larva; 

 c, pupa; d, beetles, larvse, and pupae, among scales all greatly enlarged. 

 (After Marlatt, U. S. Dept. Agr.) 



winter treatment has been neglected or has proven inefficient. 

 10 or 15 per cent kerosene emulsion, dilute miscible oils, dilute 

 lime-sulfur mixture, or whale-oil soap, 1 pound to 4 or 5 gallons, 

 may be used for summer spraying. 



On the Pacific Coast trees are very generally fumigated with 

 jiydrocyanic acid gas * for th's and other scale insects, but the 



*See C. W. Woodworth, Bulletins 122 and 152, Cal. Agr. Exp. Sta.; 

 R. S. Woglum, Bulletins 79 and 90, Bureau of Entomology, U. S. Dept. Agr. 



