234 ANNUAL EEPORTS OF DEPAETMENT OP AGRICULTURE. 



and at different times under semiarid conditions. At four localities 

 in the valley portions of orchards have been taken over by the 

 dejDartment under cooperative arrangements with growers. 



At all of these stations experiments to determine the comparative 

 merits of dusting and liquid sprays are in progress. This side of 

 the work has been especially keen at Winchester, Va., where it has 

 been shown that, with certain varieties such as the York Imperial, 

 which is little subject to apple-scab, dusting will be an effective sub- 

 stitute for spraying. 



Other apple insects. — Especial attention has been given during 

 the year to the plant-lice occurring upon apple, and particularly to a 

 certain group in wdiich much confusion exists regarding the identity 

 of species and the alternate host plants, this confusion standing in 

 the way of remedial and preventive work. Valuable results have 

 been reached. 



The work which has been carried out on the apple-tree borers 

 and other fruit-tree borers has been continued and will be brought 

 largely to a conclusion this year. Studies have also been made 

 of the apple curculio, the giant root-borer, various leafhoppers, the 

 imbricated snout-beetle, the apple maggot, and others. 



GRAPE INSECTS. 



Grape-berry moth. — In northern Ohio the grape-berry moth work 

 has been continued and materially enlarged. During the year espe- 

 cial attention has been given to the perfecting of a spray schedule 

 and to the making of improvements in methods of application of 

 sprays. There is some ground for belief that a single timely and 

 thorough spraying will be sufficient, and if so this will do away with 

 the objectionable spray residue on the fruit at harvest time. Dust- 

 ing experiments also are being carried on in connection with this 

 investigation, arsenate of lime bedng compared with arsenate of lead. 



Other grape insects. — The so-called grape mealybug has become 

 troublesome in parts of California, where its life history has been 

 studied to practical completion, and a large amount of experimental 

 work with sprays and other remedial measures has been carried 

 on. This is a difficult insect to handle, since it secretes itself under 

 shreds of bark where sprays can not rench it readily. The work on 

 the grape phylloxera has been continued on a reduced scale, the 

 effort being to determine the best means of disinfection of rooted 

 vines and cuttings tied in bundles according to the usual nursery 

 practice. A thorough survey of Fresno County, Cal., which has 

 been carried on in cooperation with the Bureau of Soils, to deter- 

 mine the relation of soil conditions to severity of phylloxera attack, 

 has been practically completed. 



,^ pecan insects. 



Additional information has been gained regarding the life his- 

 tories of important insect enemies to pecan, and especial attention 

 has been given to the use of insecticides in orchards or groves in 

 southern Georgia and Florida. Growers have actively cooperated. 

 Work of this kind has also been carried on in southern Mississippi 

 and in the vicinity of Brownwood, Tex. 



