210 Bulletin 1T6. 



As little or no gum is exuded from infested plum or prune trees, 

 the peach-tree borer is not so easily located in these trees, thus often 

 making the " digging-out " process a more laborious one in such 

 orchards. 



The " digging-out " method is, when thoroughly done, the surest 

 way of getting at and controlling the peach-tree borer yet devised, 

 and it is practically the only way to get at the pupse in the cocoon. 

 It involves much time and labor, but most other methods are equally 

 as laborious and expensive. From cur experience of six years we 

 believe that one can dig out the borers from young peach trees in a 

 cultivated orchard with no more expense and labor than it requires 

 to apply most of the other methods recommended ; on old trees or 

 on trees in uncultivated orchards we have had no experience, but 

 doubt if such conditions would much affect our belief. To prop- 

 erly apply almost any other method, one must first remove the soil 

 from around the base of the tree down to the roots, then usually 

 clean the dirt from the bark, and then incur the expense of making 

 and applying the material used. While the latter is being done one 

 can usually, with no more expense, locate and kill all the borers in 

 the tree. 



It is an interesting and curious fact that most peach-growers first 

 dig out the borers and then follow some other method, but they never 

 attribute any of the success which may follow their efforts to the 

 " digging " process where it usually rightfully belongs. Our experj- 

 ments have demonstrated to us the wisdom of certain combinations, 

 however, for the trees from which the borers were removed and 

 killed each year usually contain more borers the next year than those 

 trees from which they were first dug out and then certain other 

 methods applied.* Thus the use of certain methods to supplement 

 the " digging-out " process is not a waste of energy and is to be 



* We had to practice the 'digging-out" method in connection with all the 

 others tested. We would not have been able to make any comparison between 

 the methods without the knowledge of the actual number of borers in each tree, 

 which could be gained only by digging them out. In this process one ordinarily 

 kills many of the borers accidently, but it might be possible by taking great 

 pains to locate and count the borers without injuring them. But we doubt if 

 our experiments would have given any more conclusive results had we done this, 

 for we never lacked for a goodly supply of borers. 



