Yes, that is burl. Actually, it is tumors growing on the cambium of the tree.
The best burls for knife handles comes from root burls, but there can be some really tight curls in a trunk burl.
To harvest that you would have to cut down the tree, cut it into sections, slice the outer part off in about 6-8" thick slabs, paint all cuts wwith a good coat of house paint, and let it dry for a year ( to start with).
To see if that would be worth the effort, you can cut off a good size protrusion somewhere (Make a "V" cut to remove it) and slab it up on the bandsaw. If the slabs look good, The rest will be similar.
I would contact Mark at Burl Source for more info and advice.