16 STATE HORTICULTURAL COMMISSION. 



PEACH-TREE BORER (Sanninoidea opalescens). 



The larva of this insect is a pale-yellowish, cylindrical grub, 

 nearly an inch in length, and very destructive to the lower 

 trunk and roots of peach, almond, apricot, prune, and cherry 

 trees. Many devices and remedies have been used to check its 

 work, but none have proven entirely satisfactory. The worm- 

 ing or digging-out method, although very expensive, is no 

 doubt the most reliable one, and when followed by the appli- 



Male. 



Pupa. 



Fig. 14. Peach-root Borer {Sanninoidea opaleaceiig). 



cation of a barrier, or preventive, to keep out the new brood, 

 which is absolutely necessary, has given good results. 



In the digging-out method, the earth should be removed 

 from around the tree and wherever gum is found, the borer 

 chisel should be carefully used and the borers removed, care 

 being taken not to remove too much bark. The proper time 

 to do this is in November, December, or January. After the 

 trees have been thoroughly gone over, a barrier compound 

 should be applied. The following two mixtures have given 

 good results: 



Mixture'Np. 1. 



Unslaked lime 50 pounds. 



Whale-oil soap _ 12 pounds. 



Coal tar__ _ 14 gallons. 



To make the compound, slake the lime and tar together, 

 adding enough water to make a medium thick whitewash. 

 Dissolve the soap with hot water and add this to the lime 

 solution, using enough water with the mixture to make a 

 thick, paste-like whitewash. 



Mixture No. 2. 



Unslaked lime- -. — 50 pounds. 



Crude oil, 16° Beaume -. 3 gallons. 



Slake the lime and crude oil together, adding enough water 



to make a thick whitewash. 



The application of crude oil alone (14° or 16" Beaume) will 



