27 



placed in the original dust-container in which a little of the material re- 

 mained, were still alive after 4 hours, unless they had meantime been 

 lying directly in the dust. Such beetles survived one or two hours, but 

 then showed no signs of life. 



Summary on summer applications of contact insecticides. — The most 

 promising of the contact insecticides used as summer applications was 

 ■7J4 per cent, kerosene emulsion. The 5 per cent, emulsion gave fair 

 results when sheets were spread under the trees and the beetles which 

 fell thereon were drenched. If the emulsions had been applied about 

 the middle of April, after the hibernating adults had migrated to the 

 trees and before any considerable number of eggs had been deposited, 

 no doubt a very great reduction in the number of the new brood and in 

 injury to the foliage would have resulted. A spray api:>lied at this time, 

 when there is little foliage on the trees, would also be effective against 

 aphids. 



DESTROYING THE BEETLES IN HIBERNATION 



As has been shown previously, the adult beetles hibernate in trash 

 in the orchard, and do not go into the ground, and since the period of 

 their retirement is of long duration — from late summer to the following 

 April or May — an excellent opportunity is afforded for effective work, 

 and the following methods were given trial. 



Paradichlorobenzene . — Successful use of this material against the 

 peach-tree borer suggested its use against the a[)ple flea-weevil while in 

 hibernation, and it was scattered broadcast under the spreading branches 

 of old apple trees growing in a heavy sod-mulch. The application was 

 made April 12, a few days before the beetles left winter quarters, at 

 rates of 2, 4, 6, 8, and 12 pounds to a tree. It was evidently of no 

 value, since the beetles were quite as abundant on these trees after the 

 beetles emerged, as on their untreated neighbors. 



Hydratcd lime- — Hydrated lime at the rate of 25 and 50 pounds 

 per tree was scattered under the spreading branches of 25-year old apple 

 trees growing in heavy sod. The application was made April 27 as the 

 beetles were becoming active, and it was thought that they might perish 

 in passing through the dust, but trap cages placed over representative 

 areas under the trees so treated, collected considerable numbers of 

 beetles, indicating that the application had little if any merit. 



Fuel oil. — Trees growing in the same orchard in which the immedi- 

 ately preceding experiment was made, were treated with fuel oil spread 

 by means of a common garden-si)rinkling can at the rate of 2 and 4 

 gallons to the tree. The c|uantilies used will not properly cover such an 

 area, and the cost of a sufficient treatment would be prohibitive. Un- 

 doubtedly some beetles were destroyed, but the gross effect on the 

 beetle jwinilation of the trees was not noticeable. If the oil were applied 

 in sufficient quantity, perhaps 10 gallons per tree, control could probably 



