Spraying for the Curculio. 71 



protect against the plum curculio if they can be kept on the 

 tree or fruit. But in case of frequent rains, the jarring method 

 will not only be cheaper but much more effective." l 



Professor C. P. Gillette experimented this year apparently in 

 the same orchard formerly used by Osborn. Although the cur- 

 culio did but little injury, still "the indicated saving of fruit 

 that would have been injured in the absence of treatment was 

 44 per cent." 2 In a report of the work, attention was called 

 to the fact that reliable results cannot be obtained unless solid 

 blocks of trees are treated. 



The work done by Weed is by far the most valuable and 

 convincing of the year. A condensed account of his operations 

 during 1889 as well as 1890 is as follows : 3 



" In 1889 the cherry experiment was duplicated, the parts of 

 the orchard being reversed to eliminate any possible effect upon 

 the results that might be due to the situation. In 1888 the 

 west half was sprayed, and the east half left as a check ; in 1889 

 the east half was sprayed, and the west left as a check. London 

 purple was applied three times, in the proportion of one pound 

 to 160 gallons of water. At time of ripening, 1000 cherries 

 were picked from each of twenty-four trees in each half of the 

 orchard a total of 48,000 cherries and examined for cur- 

 culio injuries. The percentage of injury on the untreated trees 

 was 6.17, while on the treated trees it was 1.5. This gives a 

 percentage of benefit of 75.6, just .2 per cent less than in 

 1888. Plums sprayed with a combination of London purple 

 and the Bordeaux mixture matured a full crop, while unsprayed 

 trees a few rods distant lost all their fruit. The record of this 

 years' work will be found in the bulletin of the Ohio agricul- 

 tural experiment station for September, 1889 (Vol. ii. 133-143). 



" While these experiments were made as complete and satis- 

 factory as circumstances would permit, and every essential de- 

 tail was inserted in the records, they were open to three objec- 

 tions, namely : First, that while the remedy might work in a 

 region like central Ohio, where fruit-growing forms only a 

 small proportion of the agricultural interests of the inhabitants, 



1 Proc. Tenth Meeting Soc. Prom. Agric. Science, 1889, 28. Cited by Weed 

 in American Naturalist, 1891, Jan. 67. 



2 Iowa Afjric. Ea-p. Sta., 1890, May, Bull. 9, 386. 



3 American Naturalist, 1891, Jan" 70-72. 



