Trivia: The guitar that Domergue plays and that was subsequently destroyed by Ruth was a priceless antique from the 1870's on loan from the Martin Guitar Museum. Six replicas were made for the film, however Kurt Russell was misinformed and destroyed the original. Due to this the Martin Guitar Museum said they would never lend an instrument to film shoots ever again. (01:38:00 - 01:42:30)
Trivia: Towards the end of the movie. When Major Marquis runs out of ammo, in the slow motion scene. The score is taken from John Carpenter's "The Thing", another movie staring Kurt Russell.
Answer: Good catch! This should be a revealing mistake entry. The plowing was part of the set preparation. I saw several scenes in the film where the roads had obviously been plowed. It's not hard to see if you look for the small ridges left by the plow on either side of the road.