Posted: 16/10/2013 at 10:38
Honey fungus is something you have to find a way of living with. Various forestry and tree sites and the RHS have lists of trees that are less susceptible. I'd get rid of as much as you can of the willow, A dead tree is not attractive and a constant reminder of the problem.
It doesn't kill everything, I have an ash, about 7 or 8 years old, growing out of the remains of a willow that died of HF. The tree died 6 or so years ago and apart from a clematis that may have been down to HF, there have been no losses
There have been a few threads about HF on the forum recently, look back through and find them, some interesting comments and suggestions there.