Very nice looking burl.
In the 70's burl coffee tables where all the rage here in California.
My Dad spent big bucks on one, after a few months we started noticing small piles of sawdust under the coffee table.
The problem got progressively worse until one night a bug came out of it right in front of us.
It was infested with some odd little beatles.
That table became firewood.
Better luck with yours.
These guys http://en.wikipedia.org/wiki/Woodboring_beetle