I'm willing to bet that your Dad did more than a little maintainence of woodland. It has to have the brush and deadwood taken out to prevent fires and snags. It has to have selective cutting done for the health of the remainder.
As to creek maintenence, it's less often and less obvious but no less important. I can remember pulling rocks and clearing debris in the Spring on Narrows Creek.
You can ask any beautiful woman. It takes a lot of work to maintain a Natural look.