IMO...
All these hurting trees need is a reason to give up, I never been able to understand how a hole in em ain't that reason.
Once you're able to identify a shrivelly stick that ain't coming back, which is really as easy as looking, you won't have to scratch.
Don't know if Nickas just never cared to get to that point or what....
But ....well here's something I've never heard....
"I nicked this tree last week and it was still green, now it is alive and well".
Not that anyone would make a point to say it, but they never get updated, usually because Newbs find a "need" to Nick and usually the trees suck.
No one will ever scratch their $3000 tree, not because they're afraid to kill it but because at that point you're so familiar you don't have to.
Anything outside of regular pattern is enough to know what's going on. It's just experience.
So this tiny niche of trees that "should be" Nicked shouldn't even exist, so that makes the whole concept moronic to me.
Less work, less winter worry and protection, no need for nicking.
Sorce