Meet our friend, the rotting stump, which we were too lazy/cheap to remove from our yard. There's a story in that stump. You can see where the three main trunks were, one of which has rotted out faster than the other two. And because there were multiple trunks, that means this tree regrew from from a cut stump rather than sprouted from a seed.
This large poultry staple must be where a fence was attached to the tree when it was about ten years old. The tree grew completely over the nail.
The punky tree roots and stump are now home to a number of enormous grubs which I believe are some type of Longhorn Beetle larvae. These larvae have no legs and can only eat rotting wood.
There is a grub in Australia called the Witchetty Grub that looks very similar, and people eat them. BonAppetit.