I read a lot of it was used for growing timber, but the price of timber hasn't taken off like it was thought to, so a lot of it is just open forest now waiting for timber prices to rise.
Low timber prices are in part due to a supply glut due to a bunch of people deciding timber lands would be a good investment. Often it was well-off Southern families who inherited a bunch of family agricultural land that nobody in the family wanted to manage after the grandparents died, and figured planting a bunch of trees, walking away and then getting a bunch of money years later was foolproof.
There was also consolidation in the lumber mill industry creating fewer buyers for lumber an greater bargaining power on their part as a result.
It's worth noting that a lot of the tobacco land in question is owned by what amount to absentee landlords - again, the descendants of well-off planter families who now live in places like Charlotte and Atlanta.
