PEACH TWIG AND ROOT BORERS 



479 



are three. A preventive treatment consists in coating the base of the 

 tree a few inches below the surface and a foot above with a whitewash, 

 with a pint of coal tar to each five pounds of quicklime, put in while 

 the lime is slacking 1 . More recently the application of asphaltum has 

 been demonstrated by Earl Morris, horticultural commissioner of Santa 

 Clara County, to be very efficient. Hard asphaltum (grades "C" and 



Peach Worm Burrow laid open, the worm beginning spring work 

 greatly enlarged. 



"D") was applied early in the spring to badly infested trees from which 

 the borers had not been dug. A thick, heavy coating prevents both the 

 issuance and the entrance of about 95 to 98 per cent of the insects, the 

 degree of efficiency depending upon the thoroughness of the applica- 

 tion. Asphaltum does not penetrate, crack, or deteriorate, or bind the 

 tree, since it yields to the slightest pressure. 



A nearly full-grown larva of the Peach-tree Borer, Magnified four diameters. 



The material is applied warm with a brush from five inches below 

 to five inches above the ground. It is easier to apply two or more coat- 

 ings than to try to put on more at one time than will adhere firmly. 

 The first coating will harden very quickly, and the second can be ap- 

 plied without loss of time. Two coatings are generally sufficient unless 

 the bark is! very rough. But in any case, a thick uniform covering is 

 absolutely necessary for the best results. 



