When to quit ... In my Ski Patrol work some of the guys skied tobbogans (patient's life completely in your hands) well into their seventies. Tree climbing is so physically demanding and none of us will last forever. Seems in the big outfits I've met alot of Climbers who hit fifty and went to sales as they weren't comfortable aloft anymore. Personally seen fifty come and go years back and I still climb. I may not love every second of it but still git er done.