By mid-May the Nonesuch River runs warm and everything along its banks grows faster than anyone can follow — except the people whose job it is to follow it. Greencare Landscape Management takes on that climb with mowing on schedule, trimming where the mower cannot reach, and upkeep that keeps a lawn from ever getting ahead of itself. Management is the right word for it: a property looks settled because somebody is thinking a week out. When the cold stiffens the river's edges, the same attention goes into plowing driveways and clearing lots before the morning fills up. Scarborough is the center of it, reaching out toward Gorham, Buxton and Saco.