Dead trees are called widow makers.
My husband was injured a few years ago. He's cut trees his whole life and wears all the protective gear and this accident, he's alive because he had it on. Cut down a small tree with no limbs, just straight up. Went the direction he intended...gave a thumbs up when it hit....out of the blue, a limb hit him on the head..jammed his neck and back. I took him to the ER to have it xrayed and thank goodness his neck wasnt broken.
This is what happened. The tree fell, when it did, part of it tipped another tree up high. What he didnt expect was a limb from another tree to snap, spring up, then come down and land on him... He said it was weird...the tree was down, i think he had time to comment.....then boom..No helmet he would have died. Replaced his old safety helmet that was now broken, with one even safer..
Another thing i remember seeing someone do, is they put a ladder on a limb they were going to cut. Once cut, the limb jumped up after losing the weight of the part they cut off, leaving the ladder with nothing to hold it...lol
Oh, last year my guys cut up a tree that fell with its roots still attached. When they cut the tree, the roots snapped back into place. The root hole had filled with water and it was down long enough for fish and turtles to make it home....They said there were fish flopping around everywhere... but to think that someone might be standing near or at the hole, could be deadly..They knew not to because our son had watched a youtube of one snapping back.....