The force created by a powered stickie tire is far greater than I ever imagined. We used posts and logs at the Mounds and some of them were ripped loose almost immediately. I have had a tire grab a boulder the size of a refrigerator and move it. I can't imagine any way of holding a rock on a slope other than the sheer size of the rock and a firm rock base down below it. Of the places I have wheeled, only those with rocks the size of cars don't move.
GLFWDA member since 1979.
Member Southern Michigan Rock Crawlers.