Q: My loropetalum has several dying limbs. I had assumed that it had simply been stung by cold weather. However it appears I have some type of critter munching on its bark. Is there treatment or should I just start all over again? What did this?
A: At first I was certain that this was crown gall, Agribacterium tumiefacens, a bacterial disease that affects oaks trees and several other plants. However, after sending the plant sample you subsequently supplied to the UGA Plant pathology lab, I’m not so sure.
Dr. Elizabeth Little says: Judging from the shape of the wound, this could be damage from egg laying activities of certain insects such as crickets or cicadas with subsequent callus developing around the wounds.
Tree crickets lay eggs in slits in the wood similar to what I see on this branch, although I do not see the row of tiny holes in the wood down the middle of the wound. Apparently, one cicada female can make numerous wounds (5 to 20/twig) up and down the twig or branch while deposited eggs (see attached images). The slits can be long. The eggs are deposited along the sides of the wound which may contribute to the later formation of callous tissue along the edges. It looks like it may be cicada damage, at least on the small branch that you sent in. Looking back at the images sent earlier, there are very extensive areas of callous on the base and larger branches of this plant. According to what I am reading, cicadas prefer the smaller twigs (up to ~0.5″ diameter).
I’m not positive Elizabeth is correct but at this point, I’m open to further suggestions as to what’s going on.
Jim Jacobi, Extension Plant Pathology Specialist at Auburn University says: