294 SCHOOL ENTOMOLOGY 



the larvae transform to pupae from which the beetles later 

 emerge, leaving large round holes in the bark. The full- 

 grown larva is a whitish-yellow grub about three-fourths of 

 an inch long, legless, with the body segments strongly con- 

 stricted. 



The females may be prevented from egg-laying by wrap- 

 ping the trunks of the trees with wire-netting, building 

 paper, or wood veneer. Paper or wood wrappings should be 

 applied about May 1st and removed in late summer. These 

 wrappings should be tied tightly to the tree just below the 

 crotch and should extend into the soil. If wire netting is 

 used it should be held well out from the trunk by a layer of 

 cotton at the upper end. Painting the trunks with a thick 

 soap solution to every ten gallons of which has been added 

 a pint of crude carbolic acid, is said to prevent the beetles 

 from laying their eggs. Others advise a 'thick whitewash 

 to which a little cement has been added, or a paint made of 

 pure white lead and linseed oil. Such washes should be 

 applied by the middle of May and as often thereafter as 

 may be necessary to keep the bark well covered. Where 

 the borers have gotten into the heart of the tree it is difficult 

 to cut them out without damaging the tree, but they may 

 sometimes be reached by injecting a little carbon-bisulphide 

 into the burrow and stopping the opening with mud. Some- 

 times a girdled tree may be saved by bridge-grafting. 



The Flat-headed Apple-tree Borer * is more common and 

 prefers weakened or diseased trees. The larva is about one 

 inch long and the thorax is very broadly expanded so as to 

 look like the head, which gives it the name of flat-headed 

 borer. The larvae work just beneath the bark where they 

 hollow out broad flat channels, which may be detected by 

 the discoloration of the bark. The larvae become full grown 



* Chrysobothris femorata Fab. Family Buprestidce, see page 115. 



