A nor'easter reaches the heights above Dover thick and wet, the kind of snow that comes down heavy and sets like mortar. Elite Tree Services runs the winter routes through it — plowing driveways and parking areas, clearing walks and entries, spreading salt and sand where a slope makes ice dangerous. Heavy snow is a different animal from powder; it takes more passes and a steadier hand on the plow. The reward comes at daylight, when a lot that was one white sheet is squared off and open. Then the sky loads up for another one.