JJ's examples are good examples of types used for brush, wood etc. I pick up lots of cedar and locust trees in pastures after I shear them off. I use a JD utility grapple. Very similar it Bobcat's utility grapple. I like the open teeth of a utility grapple because it allows the trees/branches to fall out easy. The designs with the bar near the front between the teeth would drive me crazy with branches getting stuck on the grapple. I also need to be able to "spear" the cedar trees to pick up 2-3 at a time. If you plan an digging roots, rocks and trees out of the ground, then the styles JJ shows would be more durable.
