APPLE INSECTS — BORERS AND MISCELLANEOUS 191 



protectors not only prevent the borers from getting into the 

 tree, but also the beetles from emerging, was refuted in this 

 orchard, where the beetles sometimes emerged safely through 

 collars of brick mortar more than a quarter of an inch thick. 



In spite of the failure to control the pest in this unusually 

 severely infested orchard, the experiment did demonstrate that 

 certain preventive or deterrent measures were of value. Kero- 

 sene emulsion sprayed upon the trunks of the trees several 

 times during the summer seemed to be quite an effective deter- 

 rent. One of the best preventives tried was tarred paper 

 closely wrapped around the tree from the roots to a foot or 

 more above ground and well tied on, especially at the top. 

 Alkaline washes of any kind of soap made into a thick paint 

 with a solution of caustic potash or washing soda and about 1 

 pint of crude carbolic acid added to every 10 gallons of the 

 wash have often been used as deterrents with good results. 

 Two or three applications should be made from early May to 

 July, thoroughly covering the trunk from the branches down 

 to the roots. Instead of tarred paper, old newspapers or wire 

 mosquito netting may be used as mechanical protectors. Let 

 the netting loosely encircle the tree except at the top so the 

 beetles cannot reach the bark of the tree through the meshes. 

 These open wire protectors will last two or more seasons, while 

 the close paper ones should be removed in the fall. Some 

 orchardists make a mound of earth from five to twelve inches 

 high around the base of the trees in early spring, thus forcing 

 the beetles to lay their eggs higher up on the trunk where the 

 grubs can be more easily found and dug out. The mounds 

 should be removed in early autumn. A combination of this 

 mounding system or a wire or paper protector with the applica- 

 tions of a deterrent wash above the protector if thoroughly 

 done should effectually prevent many of the borers from getting 

 into the trees. 



Clean culture is one of the best preventive measures. Do 



