590 



INSECT PESTS OF FARM, GARDEN AND ORCHARD 



out into the bark, often cutting clear across a tree. The upper 

 part of the burrows are stuffed with fine borings and the lower 

 part with long wood fibres. The full-grown larva is a light 

 yellowish, cylindrical grub, about three-quarters inch long. The 

 head is small, legs are lacking, and the body .tapers gradually 

 from the thorax backward, the segments being quite constricted. 

 The third spring the larvae transform to pupse and about three 

 weeks later the adult beetles emerge through large round holes. 



Control. The females may be prevented from laying their 

 eggs by wrapping the trunks with wire netting, building paper, 



FIG. 445. Work of the round-headed apple-tree borer: a, puncture in 

 which egg is laid; 6, same in section; e, hole from which beetle has 

 emerged; /, same in section; g, pupa in its cell. (After RilejO 



or wood veneer. If non-rusting wire netting is used it may be 

 left on and will also protect the trees from mice and rabbits. 

 The paper or wood wrappings should be applied about May 1st, 

 and removed in late summer. They should be tied to the tree 

 tightly just below the crotch and should extend an inch or two 

 into the soil below. The wire netting should be held out from 

 the trunk of the tree by a layer of cotton batting under it at the 

 upper end. Various washes have been used to repel the beetles. 

 Thick whale-oil or caustic soft-soap to which a pint of crude 

 carbolic acid is added to every 10 gallons is often used and should 



