So, it would be second-growth, third? what, then, to account for 2000 trees/acre...? I have around me, in four national and state forests, just such a density and it amounts to 5-10 yr saplings competing fiercely for space and light--most will never make it. It is the early pines and poplars growing after crude "non-realtor's" clearcutting--They arrive immediately after the blackberries. I get as upset as anyone at crude logging techniques, mostly because of the longterm damage to soil and waterways, but at least it creates some space for the firetrucks to get in.
What I fear is the standing turpentine debris of the wasted pines that linger in huge rotting piles, not the density of the new growth. I wish on a rainy day we could have a few national bonfires to dispose of the fuel. The saplings will crowd themselves out soon enough, as can be seen in the 20-yr forests.
I thought after our long drought that we were in for some ghastly fires, but the rains finally came. The growth in this past year has been amazing. The mountain laurel this past spring was the best I'd seen in a decade--they are such drinkers and so picky, it's a good sign when they're happy.
And I've never understood about the positive habitat assertions of low density. Critters and birds are crazy for the undergrowth. The oldest forest parks, like at Winterthur, are quiet of life.
You need a mix. The owls and hawks need open flight paths. The groundcovers need light and can't survive a heavy needle drop. A few thickets in open areas serve as breeding places for critters, and then there are meadows that have the largest variety of creatures and plants while providing a place to hide out during a fire.
Complexity is where it's at.