20 DECIDUOUS FRUIT INSECTS AND INSECTICIDES, 



2 to 5 inches below the surface of the ground and maj' be readily 

 destroyed by thorough plowing and cultivation during the summer 

 and fall. 



DEMONSTRATION WORK IN CANKER-WORM CONTROL. 



For several years the spring canker-worm has been quite trouble- 

 some in a few old orchards in northern Virginia and very little head- 

 way had been made by the owners of the orchards in its control. In 

 the spring of 1905 Dr. John S. Lupton, of Winchester, Va., desired 

 the assistance of the Bureau of Entomology in freeing from this pest 

 his large orchard of SO-j^ear-old Newton pippin trees, which had been 

 defoliated to a greater or less extent for three or four seasons. The 

 orchard had been in sod for years and no recent spraying had 

 been done for the codling moth. Under these conditions the canker- 

 worms had been able to multiply with practically no interfer- 

 ence and had become exceedingly abundant, 50 per cent of the trees 

 being practically defoliated and the others more or less so. A plan 

 of treatment was submitted to Doctor Lupton, which was carried out 

 by him under the writer's supervision. This treatment consisted in 

 a thorough spraying of the orchard with Paris green at the rate of 

 1 pound to 75 gallons of water (plenty of lime being added to lessen 

 danger of injury to the foliage), the thorough plowing of the orchard 

 during the early summer, and its subsequent cultivation during that 

 season. Only one application of poison was made, and not until 

 much later than was desirable, the larvsc being already from one-half 

 to three-fourths grown, many trees having been practically defoliated. 

 Xevertheless, the treatment checked further defoliation and within two 

 to three days the larva3 had largely disappeared. That the majority 

 were poisoned was evident, since upon later examinations pupa' were 

 exceedingly scarce, even under trees from which the leaves had been 

 almost stripped. During early August the orchard was thoroughly 

 plowed, special pains being taken to break up the soil under the 

 trees. Late in the fall the worst infested portion of the orchard was 

 again 2:)lowed, and at right angles to the direction followed in the 

 first ])lowing. The rest was plowed early the following spring, the 

 whole being prepared for corn, which later was planted, receiving 

 necessary cultivation during lOOG. As was (piite evident in the spring 

 of lOOC), (lie thorough spraying with Pai'is green and plowing of the 

 orchard had destroyed the great majority of the insects. In the early 

 spring of 1906 bands of a sticky preparation i)laced around the 

 trunks of trees Avhicli had been practically defoliated in 1905 caught 

 not more than two dozen specimens of adults in all, and larvir were 

 very difficult to find later. That the absence of the insects in this 

 orchard is to be attributed solely to the spraying and plowing and 

 jiot to unfavorable weather conditions or the inlluence of parasitic 



