I had a huge old pine tree in my front yard that was naturally split into two straight trunks from a single trunk. During a huge ice storm, one half of the tree fell over and pounded my neighbor's tiny Japanese maple into the ground like a tent peg, and the other half, no longer counter-balanced, gently leaned against my house. When they started cutting it up with chain saws, sparks started shooting, so they had to finish it up with an axe. They assumed lots of nails were in the tree.

Turned out some time in the ancient past, someone put up Christmas lights in it and never took them down, so now all the wires had grown *into* the tree. Like you could cut disks of it from the trunk, and see the old wires and bulb sockets among the rings.