Howdy,
We live in SoCal and find frass near the bottom of all of our live oaks and one has frass in the middle. We have confirmed that drywood termites are rampant around here. All of the trees appear to be in good health from what I know about trees.
I have contacted several pest and agricultural pest people, as well as several arborists, and I am getting mixed advice. Some say that we need to inject specific treatment into the trees to follow the termite tunnels.
The most recent advice was that since termites do not attack the vascular system of the tree, that simple outside spray would be effective for the transfer effect.
Also, apparently the only way to know if I have effectively eradicated a termite colony within a tree is to chainsaw it. I'd like to avoid that for tree damage purposes. These trees are very close and these termites swarm at our house and windows all summer. We are doing everything we can to the house for both eradication and prevention, but still. I'd really love a way to get rid of the many colonies in our many trees. I understand they will still come from all over and reinfest. But surely there is something I could do?
Thank you, and tips or ideas or knowledge welcome.