Bunter...  If you have around 40 trees around the house I would suggest you need to do something p.d.q.  The linked article talks about the weevils "walking" from tree to tree.  Apparently they can fly up to 3 Km from tree to tree.
Rita ....  I guess it's easy to lay blame but I'm appalled that Gencat didn't do something to prevent this years ago.  I'm not usually one to run down the "locals" but it appears that the attitude taken is fairly typical.