ORCHARD INSECTS OF THE PACIFIC NORTHWEST 



39 



generation of the white leafhopper, and in late July or August for the 

 second generation of the latter. The nicotine spray may often be 

 combined with an oil emulsion and used in place of one of the applica- 

 tions of lead arsenate for the codling moth. The lime-sulfur spray, 

 which is used in May in some districts for apple scab or powdery 

 mildew (table 1, p. 71), constitutes an excellent control for leafhoppers, 

 and when it is used nicotine sulfate should not be needed. 



Syneta Leaf Beetle 



The syneta leaf beetle {Syneta albida Lee.) seldom injures apples, 

 but may cause a reduction of 50 percent or more in the pear crop. 



Figure 46. — Young pears injured by the syneta leaf beetle. 



The injury consists of scars and deformities on the fruit, caused by 

 the beetles when feeding. The beetle also chews the fruit stems (fig. 

 46), and causes some of the fruit to drop. Practically all of the injury 

 is done during April and May. The life history of the beetle is dis- 

 cussed on page 49. 



CONTROL 



Good control of the beetles on apples and pears may often be 

 obtained by a single thorough application of lead arsenate at the rate 

 of 3 pounds to 100 gallons of water used as a calyx spray. If the 

 infestation is severe a second application may be made 10 days or 2 

 weeks later. 



Western Tent Caterpillar 



The western tent caterpillar (Malacosoma pluvialis (Dyar))is prac- 

 tically limited in its depredations to the region west of the Cascade 

 Mountains. The caterpillars appear in May and June, constructing 



