Been getting pretty bad around here as well, quite a lot of crap / mud on the roads from tractors.

Given the oversize nature of most of these tractors and the supersize trailers / tanks etc that they tow around, they pick up a lot of mud in the fields which gets distributed all over the roads.

TBH I dont think they care about what they leave on the roads.

Had a big shit tanker going along the opposite side of the road to me during the summer, and the outlet was weeping so everything on my side of the road was getting a light spray of crap.