There are folks that use green hickory, pecan and even mesquite, you have to have a very hot fire, and a large cooker helps. The trick is to build a clean hot fire with seasoned wood or charcoal, them add just enough green wood to ignite and burn.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
Whip It Off, Chambers!
"perhaps...but then again...maybe not..."