Across from Ossining the Hudson spreads into its widest reach, and whatever weather is building over the Rockland shore gets here soon after. That open water is why winter arrives with a push behind it — the flakes come in sideways and pile against the north side of every driveway. Ac Contracting And Landscaping plows and shovels through those nights, salting the walks so a doorstep is walkable by the time coffee is poured. When the ice lets go in March the same crew turns to mowing, trimming and cleanups, following the season back up the hill. Two kinds of work, one town, and a standing promise to whoever is waiting for the driveway to open.