Green Edge Landscaping of Scarsdale keeps two calendars. The green one runs from the first mow of April to the last cleanup of November: grass cut, beds shaped, a trimmed border following the curb block after block. The white one starts whenever the timber-and-stucco storefronts downtown pick up an inch overnight — plowing driveways, shoveling walks, laying salt before the village is properly awake. Between the two there is barely a gap, and that suits a town built on hills where the weather makes itself obvious. What holds steady in both is the finish: a straight line where the work stops, whether it is cut into grass or scraped down to blacktop.