I have no proof of this, but my gut tells me that in a few years we will learn that underground CO2 kills trees and turns the forests into barren waste-lands.
Isn’t underground carbon sequestration essential how the process occurs naturally?
CO2 does not naturally push up from large underground pockets, at least not very often.
Why not in the nation’s forests? Plant some trees?
There are already trees there, it's hard to add much more on the same terrain and you would need to expand the forests to already occupied lands. If you removed the land use, those forests would probably spread by themselves in only ~300 years.