588 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



kerosene emulsion or dilute tobacco extract should be applied, 

 using two or three gallons per tree, or enough to thoroughly 

 wet the soil. Dilute miscible oil might be used in the same way. 

 Boiling hot water may be similarly applied, but is hardly prac- 

 ticable for extensive use. Carbon bisulfide injected into the soil 

 has been frequently recommended, but practical tests do not seem 

 to demonstrate its efficiency. Badly infested nursery stock should 

 be destroyed, and it will be a good practiceto dip all trees in hot 

 soap solution, or lime-sulfur wash, to destroy any aphides as well 

 as San Jose scale. It has been observed that trees grown on 

 Northern Spy stock do not seem to be as badly injured, and the 

 matter of the susceptibility of varieties should receive further study. 



The Round-headed Apple-tree Borer * 



The young apple orchard must be given frequent inspection 

 to detect the work of the round-headed borers, for if they become 

 established in the young trees it is difficult to kill them and they 

 soon girdle the trunks. They are most injurious to apple and 

 quince, less so to pear, and also infest wild thornapple trees and 

 mountain ash. The species occurs generally east of the Rocky 

 Mountains, but is not commonly injurious in the Gulf States! 

 The presence of the borers may be detected by the retarded growth 

 of the trees, with a yellowing of the foliage, and the sawdust like 

 castings which the larvse throw out from the entrances of their 

 burrows, accompanied by a discoloration of the bark over the 

 new burrows, and in early spring there is often a slight exudation 

 of sap. Injury is most severe in neglected orchards, where grass 

 and weeds are allowed to grow about the bases of the trees, as 

 the beetle, which flies at night, seeks the concealment of the rank 

 vegetation during the day. The parent beetle is a handsome 

 insect about three-quarters inch long. The antenna and legs are 

 gray, the head and under surface of the body silvery white, and 

 the upper surface is light brown with two longitudinal white stripes. 



* Saperda Candida Fab. Family Cerambycidoe. See F. H. Chittenden, 

 Circular 32, Division of Entomology, U. S. Dept. Agr.; E. P. Felt, Bulletin 

 74, N. Y. State Museum, p. 23, which gives full bibliography to 1902. 



