By Sylviagiles
Dorset,
United Kingdom 
I don't know what to do about the insects eating my twisted willow tree. We had to cut off half the tree because it was dead but the other branch is alive and has green leaves on it. I would like to save it.
2 May, 2016
Answers
Woodlice are doing no harm to the tree, but it looks like the trunk was attacked by some form of borer, if you have those in Dorset.
3 May, 2016
yes we do have wood borers. some pretty spectacular ones too.
3 May, 2016
Well, in my experience, the only thing that will kill borers once they are in the tree is systemic insecticides. It is one of the few situations in which it may be safe to use neonicotinoids, since, as far as I know, willow catkins don't attract bees.
4 May, 2016
looking at the photo they look like woodlice. [a crustacean rather than an insect] they are feeding on the dead wood. Trying to get rid of them will be a loosing battle though.
2 May, 2016