Tree work pays all the bills.
Sellin firewood is the tree-related side job.
I do some welding for people around here on a semi-regular basis.
Once in a while my former boss contracts me to do high ropes course/rock climbing instructor work when they're short handed. They spent several years training me, re-training me, rescue training me.... then I started a tree business.
At least all that training went to some good use...
I enjoy workin with people though, and teaching, so it's nice to do once in a while.