I was working for a black bear guide in northern alberta in the early nineties for a month. We were baiting and searching new areas. As we came over a grassy knoll, there was a griz on full alert about 100 yards away looking at us. We both instantly looked around for trees, and looking back noticed it was running full tilt towards us. I went left, he went right, and the bear luckily went after him. I climbed some poplars growing close together, he went for a hemlock a bit farther away. He jumped for the higher limbs to pull up but missed on the first try. The bear was right about on him. He JUST pulled up into the tree and the bear tore the bottom of his rubber boot off, only leaving minor bleeding on his foot. He climbed high and I could hear him laughing and mocking the bear. He then urinated on the bear, again totally mocking it.
I was scared sh*&^less. The bear never looked my way, hung around for about an hour and lumbered off.
He hung the boot up in camp for the next several years that I knew and hunted with him.