Late October turns the long green corridor of the Old Croton Aqueduct into something copper and loud underfoot. Tigre Tree Care and Landscaping Inc. works the yards on either side of it — mowing while the grass still pushes, then hauling away the leaf fall that arrives by the truckload once the maples finally let go. Come the turn of the year those same trucks carry blades, and the crews are out on Greenburgh's steep, curving drives moving snow before daylight reaches Woodlands Lake. This is a town of hills, which means every property has its own stubborn angle and its own place where the drift piles up. Learning those angles is most of the job; the payoff is a lawn that reads even in September and a drive that opens wide in February.