Boring Insects (“Borers”)

Quick Facts

Far from being dull, these flying beetles get their name from parasitically boring into the living wood of host trees and siphoning out nutrients over time. Yuck? Totally! 

Keeping your trees happy, healthy, and well nurtured is the key to preventing these pests, and our team of certified arborists and experienced plant health care professionals can treat to aid in suppression if the beetles have moved in.


Prevention by keeping a healthy tree is best!

If your tree is experiencing borers, our arborists can apply a systemic treatment injected into the soil to help suppress the boring insects.

In most cases, the infected tree should be able to live a typical lifespan with consistent suppression and general wellness care.


Keeping trees strong and healthy is the only true prevention for boring insect infestations.

Certain trees, like Swan Hill Olives, shouldn’t be pruned during the flight months of the boring beetles (April-September). This is because pruning can weaken the tree during the peak months of the beetles’ search. The best way to avoid this is to simply wait for pruning on these specific trees until the off-peak season. 

In most cases, your best shot at prevention is keeping a well-watered, well-fertilized tree and having your arborist out at least yearly to take an expert look for any signs of borers so we can begin suppression treatments. 

Signs & Symptoms

Signs of a borer infestation are small globs of pitch, frass, and general tree dieback as the boring insects siphon nutrients.

Target Trees & Plants

All varieties of Pine in the Sacramento Valley

Swan Hill Olives

Boring Beetles are opportunistic insects that feed on weak and stressed trees. They don’t discriminate between specific varieties of trees, and will find a host tree that is an easy target. 

Have questions, or need help pruning, planting, or caring for your plants and trees?  Schedule a visit with one of our ISA Certified Arborists!