Yeah the first UK sightings were only a few years ago but like so many introduced organisms it has spread like wildfire. Not really that harmful (yet) but plenty are.

If (as predicted) we get Emerald Ash Borer then the few ash trees that don't succumb to chalara will be killed off by the borer.

Certainly scary times for trees. I guess I'm at 10,000 plus planted now, be interesting to see what's still prospering in 20 yrs.