Bitternut hickory, Carya cordiformis. I lack a burl sample in my collection. Willing to trade or buy a lab for a sample. Often times, the wood under the burl on the other side of the portion you cut off has figure deep enough into the trunk to work for my samples.
Sorry Dan, somehow missed your post. Must be the holiday influence...
There were some smaller burls on the tree I may post for sale in the future. I will give you first dibs.. What was the identifying characteristic that gave it away the orange yellow cambium layer?