Divots? Or muddy tire tracks? Same thing as before, or something new?
It's the remnants of the tire tracks, where they cross the line - they appear to be about 2 feet long. The grass clearly hasn't recovered on those spots yet.
Those spots are where the damage was sufficient to get to the soil; although truth be told, the paths in the grass further along the line (5-10m) were still visible too.
At this point I'm reverting to calling them tire tracks.