1. SOME COOPERATIVE SPRAYING EXPERIMENTS 



AGAINST THE PLUM AND QUINCE 



CURCULIOS 



In my report as Chairman of the Committee on Entomology to the 

 New York State Fruit-Growers' Association in January, 1904, I gave the 

 details of some successful experiments made in 1903 by Mr. J. W. Spen- 

 cer, Westfield, N. Y., and Mr. A. I. Loop, North East, Pa., in controlling 

 the plum curculio with poison sprays. Mr. Loop used the arsenate of lead 

 (3 pounds in 50 gallons Bordeaux) and the arsenite of lime (3 pints 

 standard mixture in 50 gallons Bordeaux) and made two applications on 

 several varieties of 

 plums just after the 

 fruit had set and two 

 weeks later. The in- 

 jury from the curculio 

 on his sprayed trees 

 was practically noth- 

 ing, while on adjoin- 

 ing unsprayed trees 

 from 80 to 85 per cent 

 of the fruit dropped 

 from curculio injury. 

 His neighbors com- 

 plained of consider- 

 able injury from the 

 insect and they kept 

 " curculio catchers " 

 going and got many 

 beetles, while Mr. 

 Loop could get only 

 one or two beetles per tree after the first spraying. 



Mr. Spencer, sprayed peaches, cherries and plums three times, soon 

 after the petals fell and at intervals of six and ten days later. I exam- 

 ined the trees and there was much less of the work of the curculio on 

 all tlic sprayed trees as compared with unsprayed trees left as checks. 



These experiments aroused much interest among the members of the 

 Fruit-Growers' Association and in consequence I concluded to try and 

 interest several fruit-growers in cooperative experiments against this arch 

 enemy of the stone fruits. My efforts met with much success and in 1904 

 more than twenty leading New York fruit-growers cooperated in spray- 

 ing experiments against the plum curculio, and the plans were extended 



IS9 



Fig. 39. — A " curciilio-catchcr" at.zvork. 



