Elsewhere there are discussions about the feasibility of killing bugs with ultrasound. All of those discussions consider a situation, presumably, where the bugs are in the air. That seems a tricky problem, but perhaps not the one I wish to discuss. The Problem: So in California we have this infestation of exotic beetles which are killing oak trees in large numbers. Their cycle is such that they feed on oak leaves, fly around, and breed in the late spring and summer. Most of the winter and spring is spent either eating oak wood underneath the bark or pupating etc. Poison works to varying degrees, but it is pure maintenance and cannot be used to completely eradicate beetles from a given area. It can also be expensive. I am wondering if these beetles can be killed with sound when they are pupa sandwiched between tree bark and tree trunk. I thought maybe microwaves, but that doesn't seem feasible without also maybe killing the tree. But sound seems plausible. I wonder if you need to reach the resonant frequency (yes you can span a range of frequencies maybe quickly to reach all the resonant frequencies in the body, whether that has the desired effect I don't know), or if you can make up for lack of resonant frequency with amplitude? Especially if perhaps you can make the tree into a sounding board whereby you might transform, say, a 150 db sound into something much, much louder? And you need not kill the beetles, just incapacitate them so that they can't breed.