Now that would explain the damages. Here we pickup and keep our lawns clear of the rocks. Sometimes we use to build rock fences; other times we used for back fills to provide drainage. Beside we use our lawns for playing and other activities where rocks, trees limbs, etc can cause avoidable injuries.
Personally I have weak ankles and need support for them. Even with the support there are times I nearly sprain them just walking across my lawn or stepping off a parking lot raised lip.
Now I do have a 48" rotary cutter with swing arm like those disc cutters used over there. They take a beating with heavy blades but even get damage from constant rock impacts and we need anti sail covers in place especially to protect the operator. I personally seen rocks swung up to 50+ feet by my cutter which is why I make sure no one including my farm animals are around when I am cutting an unknown area. Rock do have a habit of showing up at times in the pastures too where their were none before.
