I always kept a small knife attached to the harness strap where it was easy to get to if needed to cut the strap.
I've used climbers, chain/strap on and ladder stands. At one point I even used a 1x10 board with "V" notches on each end to wedge into the crotch of a tree, the latter I would not recommend. I do use ladder stands now but I don't hunt much anymore.