This is what PNW forests are supposed to look like.
Notice all the downed wood that is rotting to create new soil. Leaving most of it to rot, with occasional fire that liberates other nutrients and, as someone said allows different seeds to germinate, is what is required. Note also the large old trees (and their thick layer of ancient lichen) that trap moisture.
Removing wood in any form, whether clearcutting or thinning, destroys the soil. This can be to a greater or lesser extent depending on what equipment is used, but the fact is you are taking a lot of carbon out of the system and where is that going to be replaced from?
We got into the fire suppression game because people thought that if they suppressed all the fires, then they could remove the wood themselves and use it for lumber. That has not worked out. It has led to billions of acres of forests that are fire prone just because they are young.
Young forests are made of kindling. Trees with thin trunks, lots of brush, a forest floor that is missing its foot-deep layer of damp rotting wood, a canopy that is too thin to retain the moisture and shade the ground.
I don't know what the solution is. I suppose we could desalinate a lot of ocean water and hose down the forests every couple weeks to replicate the water retention that old growth parent trees would have provided. That would be insanely expensive and probably have some kind of negative effect on the oceans.
