Plum Tree Murdered by Borers

Q. I have murdered my 5 year old Santa Rosa plum. The borers have finished it. I treated the tree for iron twice earlier in the spring, and It never seemed to help, I now see why. They are in every branch, and looks like the main trunk. I had white washed as you suggested, but I should have reapplied every year, since it faded some, and of course the tree grew. I have learned a valuable lesson, and I feel terrible for the loss of my tree. Thank god, I had a bumper crop last year, hopefully I have enough jam to hold me a few years until a new tree takes shape. Thank you so much for years of tips and tricks for our garden.

Santa Rosa plum ripe

A. So many borers as you stated is an indicator that perhaps the branches were getting overly heated and burned by the sun. Always keep a full canopy to shade the limbs and trunk. Pruning fruit trees in the desert is an art. It is finding a fine balance between removing enough and removing too much wood from a tree.

Sap oozing from cut limb on plum. Sap oozes freely from damaged limbs on plum. This is a defense mechanism and when working properly drowns any infesting insect with sap.

Never prune so much that it opens up the canopy for sunburn to the limbs. Mulch the soil which helps keep a full canopy and dig out borers as you see them causing sap oozing from the trunk or have limb dieback. I will do this in the winter time when all the leaves are gone and it is easy to find damaged limbs.