This is a gorgeous stump. What's more - I actually know what kind of tree this is. So, bonus points for me because generally I have no idea whatsoever what a tree is unless it has leaves. I'm good at leaves.
Game rules: Tell me what you can about the tree from these pics.
Here's a close up of the stuff going on in the center.
We're guessing ants, but that's just a guess.
If you want a hint, there's a pic of the logs below the fold.
Here's a pic of the logs. If you are at all familiar with midwest trees, then these are a dead giveaway.