The way I do it is I keep my grapple and loader on the tractor and set the grapple just off the ground. Then knock down the tree's or sapplings and drive over them. The tractor has the advantage over the skid in the ground clearance dept and on the skid the cutter finds all the hidden goodies in the field first. One account I have had kids playing paintball in the field. They had setup pallet forts to hide behind. The grass had over grown them but a foot or more. The grapple finds them way before the cutter. So it's a win win for me. I don't know what dealers are close to you but go to the woods site and do a dealer search. Same with the other brands. My dealer is in Colchester Ct, DH Marvin.
Ask for Curtis but there maybe closed dealers to you.
My Bush Hog sticks out 3+ feet to either side of my tractor so I just use the wing and don't actually drive over the material first. If I was using a smaller cutter I would back in to the mess....For something of that size a Skid Steer would be the best option.