If your plan is to ultimately run cattle, consider silvopasture (as others have suggested). I’ve used cattle to clear brushy woods, albeit on a much smaller scale, and it was fascinating to watch the land evolve from dense woods to open pasture with scattered trees. It did take time, however. I fenced in a paddock, put the animals in there for a week (the paddock contained open field so they had whatever grass they needed along with lots of wooded area), and moved them to another such area. The fencing was single-strand electric running ~8,000 volts. Never had them escape. Brought them back to the area a few weeks later…rinse and repeat. By the end of the grazing season they had opened up the forest to the point I could, over the winter, cut down any trash trees and thin out everything else to the desired density. Beautiful grass and lots of shade…looked like a park after a couple of years, with no soil erosion or pugging. Studies of silvopasture have found that up to 40% shade cover does not impinge on forage production and, when used in conjunction with planned rotational grazing, can dramatically improve the soil and hence the forage and beef production. Look into Allan Savory, Ian Mitchell-Innes, and others.
