276 Repout of the Depautmext of Entomology op the 



treatment. 



Sources of infestation. — The insect breeds readily in dying and 

 dead wood. Weakened trees, especially peach, plum and cherry, 

 often haibo.r the beetles and if not removed may cause the infes- 

 tation, of neighboring trees. Small branches trimmed from the 

 trees may become the sources of infestation. A case in point is 

 the orchard of Globe peach trees near Youngstown, previously 

 referred to. ^yithout doubt this orchard became infested from a 

 large pile of dead branches within about a rod of the corner tree 

 in the northvrest corner of the orchard. The beetles were breed- 

 ing iuf the branches early in the season. During August about 

 twenty trees in the corner of the orchard nearest the brush pile 

 were found infested, the presence of the beetles being indicated 

 by the exudation of sap. The worst infested trees were nearest 

 the brush pile. 



Suggestions for late summer and icinter treatment. — The ha;bits 

 of the beetles, when attacking normal trees, suggest two methods 

 of treatment: First, the liberal application, about the middle of 

 July, of some caustic wash, such as a solution of whale-oil soap, 

 two pounds to the gallon of water, with the addition of crude 

 carbolic acid, two ounces to the gallon of tlie soap solution. The 

 whole should be well stirred before using, as otherwise the car- 

 bolic acid and soap solution will not mix well. Probably two 

 applications about ten da^-s apart will be sufficient. The object 

 of the applications at this time is to prevent the beetles from 

 going into the bark. Second, severe winter pruning. This is 

 to destroy the eggs and hibernating larvse and beetles in the 

 twigs. The infested branches can be distinguished by the exuda- 

 tion of sap as shown at Plate XXXVII, Fig. 3. The pruned 

 branches should be burned. 



