When we clearcut areas, we leave the not dying ones for exactly that reason.
I spent the day marking timber for falling at Ledreborg forest distrikt.
Came across 3 wet areas with large stands of ash.
They were in so bad shape, that instead of marking individual trees, I just wrote "clearcut" on the trees at the border of the areas.
Terrible!
I like marking trees BTW. You get to see a LOT of forest that way and it shows that the owners trust you, since it takes a lot of integrity to mark trees in selective loging, that your own outfit are going to be cutting.
Plus, a spraycan is way lighter than a chainsaw to lug around.