Late September on the west bank of the Hudson turns the Highlands rust and amber, and the yards below Route 9W begin filling with leaves faster than anyone can keep up. Nargi Landscaping keeps up. The mowing carries through the last warm weeks with edges held tight along drives and walks, and then the cleanup work begins in earnest — leaves off the turf, corners cleared, beds tidied ahead of the cold. Working ground this steep and rocky means smaller passes and more care, and the finished lawns show it. By the time the oaks let go of the last of it, the properties are put away neat for winter.