when i was living in texas a couple of years ago, a tanker truck with a boom and nozzles (like the kind that sprays tar when laying the road) used to oil down the sand roads, making them into a road that was really close to a paved one. i know it's texas, and there's oil on the ground everywhere, but it did seem a bit "dated" seeing roads sprayed with oil, then rolled.

railroads used to get a tank car, and a pumpcar with fire nozzles on it, and they mixed weedkiller with kerosene, used oil, whatever. the petroleum helped the weed killer stick, and they would spray everything with it. the right of way used to be widely cleared, and it was nice for running. most right of ways now have the growth right up to the ballast now, and getting smacked with trees and branches is a daily deal. hooray for oil and weedkiller!!