Our yard keeps sloping down into the woods, at the bottom of the slope is a dry stream bed, which is actually marshy most of the summer. Then it slopes up to the farm field. The woods, here in maryland, get very vine covered, lots of thorny vines, wild brambles, berries, etc. Also a ton of poison ivy. We could go in there and clean the vines, downed trees, ivy (well I couldn't cause of the ivy) it would take days, weeks, maybe months. For what? so nope we are leaving them for the critters. The deer bed down in the woods, rabbits, ground hogs, squirrels, birds and anything else around just love them.
I have more than enough land to play with, that is their play ground.