Unless you have a backhoe or a FEL shovel attachment, hooking a chain around them and pulling them up by the roots is the best way to go especially with the sweet gum trees. ANY amount of root left is going to sprout out a tree, but these can be dealt with via chemical spraying (2-4D) or just mowing them down each year. Thorn trees are the worst for sprouting and also have the most tenacious root system. I found a couple of them growing outside my fence line in the road ditch right of way so rather than cut them with my weedeater with Gator head attachment, I took my
B26 out and dug them up with the back hoe. They were about 20 feet apart and all on a connected root about 4" in diameter with all kinds of root spurs coming off. Nasty rascals to control.
I had a section by my creek that was about 60 feet wide by 800 feet long that was very thick with sweet gum trees that I used my tractor and bush hog to push over and shred up as much as I could get into the thicket which worked fairly well till I got too many large trees in the way but it did thin out along the edge. After about 3 years of mowing most of the stubs had died and rotted out. I also used my RTV 900 and a chain to yank out a bunch of the smaller ones which got a lot of them thinned out. This was a lot of work, hooking, pulling unhooking etc but it was still faster than digging them out with the FEL and it left much smaller holes.
After I got my
B26 TLB, I made a half day clearing out and thinning enough that I could get my tractor around thru them. I didn't want to take all, just enough to allow some light to get to the bottom so some grass could grow. I just backed up into the thicket, popping them out left, center and right, then used the backhoe thumb to drag them to the side and stack them, then backed in for another round. About 6 hours of this and I had almost all of what I wanted to remove on the ground, then it was just a matter of pushing everything into a pile for burning later. A backhoe is an expensive attachment, but I wouldn't be without mine. I just wish I had bought one 4 years ago rather than last year. I have not only cleared sapling growth, but dug up dead and live pines trees from sapling size to greater than 20" diameter at the butt end, dug up rocks both large and small, dug pits for burying dead animals, mucked out ponds and creeks to remove trash and make deep holes in my creek so they stay wet year round, hauled dirt to fill in holes, etc. Just tons of uses for a TLB but only if you can justify the upfront costs with a substantial amount of work.