To summarize the results of dozens of rolls, the model boulders produced either zig-zag tracks from corner-over-corner rolling or longer tracks with a helical pattern from face-over-face rolling. When I searched YouTube for videos of rolling boulders to try to better understand the origin of the diagonal gouge marks, I repeatedly found “boulder trundle” videos. The boulder’s tree scarring and faint slope track appeared to begin just below the base of one such felled oak, suggesting the rolling of the boulder was indeed a natural, storm-induced “trundle.”