6 MAINE AGRICULTURAL EXPERIMENT STATION. 



METHODS OF CONTROL. 



After borers have once entered a tree there is no better 

 remedy known than to cut them out with a knife or other sharp 

 instrument. Cutting the borers out, unless practiced with the 

 greatest care, is apt to result in injury, and it is far better to 

 prevent the parent insects from depositing their eggs upon the 

 tree. This is not difficult of accomplishment, as oviposition is 

 practically confined to two months in any single locality, usually 

 June and July. The best preventives are impenetrable sub- 

 stances placed about the trunk and various washes of a repellant 

 nature. 



For this a few thicknesses of newspaper wrapped rather 

 loosely about the trunk and extending about two feet from the 

 base are all that is necessary. This covering should be tied, by 

 preference with cord, which will readily yield or break with the 

 natural expansion of the tree in its growth, and also be tightly 

 fastened at top and bottom and hilled up with earth so that the 

 beetles cannot obtain access to the tree from below. From the 

 top of this covering upward it is best to use some deterrent alka- 

 line or carbolated wash. 



Any one of several washes in general use against boring 

 insects may be used as a deterrent. A good alkaline wash is 

 prepared of soft soap reduced to the consistency of thick paint by 

 the addition of caustic potash or washing soda in solution. A 

 good fish-oil, or whale-oil soap, or common soft soap, is often 

 used, and in some cases any one of these is sufficient to deter the 

 insects from depositing their eggs. The alkaline wash may be 

 carbolated, if desired, by the addition of crude carbolic acid, 

 at the rate of i pint to every 10 gallons of the wash. Such a 

 wash not only affords protection against this and other borers, 

 but against scale and fungous diseases at these points, and is, 

 moreover, of positive benefit to the tree. Caustic potash fish- 

 oil soaps are among the best for insecticides. 



Clean culture is an important measure as an accumulation of 

 weeds or water-sprouts about the base of the tree constitutes a 

 favorable situation for the females at egg laying time. 



