Saw this wood for sale, claiming it is Black Walnut. There are walnuts all over the ground around it. I looked at the tree today. The smaller branches look like Silver Maple. The main stem is 40' long and about 3' at the base. I don't see another tree around it. I've never seen BW bark like this. The heartwood is only about 12" and is not dark like Walnut I'm used to. Any ideas?