Good evening and thank you for your question.  From your photo, I am not seeing any signs or symptoms for peach tree borer damage (sap oozing from base of tree, sawdust like frass, insect pupae, etc).  It may not even be an insect.  How old are the trees, what do the leaves look like?  For the most accurate diagnosis, you may need to hire a reputable tree service to come out and inspect your trees.  

Here is a factsheet on peach tree borers for your reference:  
https://entomology.ca.uky.edu/ef200
 
Please let me know if you have any further questions.  Thank you.