On the northeast corner of Yonkers, where Kimball Avenue's blocks run tight to the city line, a Saturday in July starts with mower engines answering each other down the street. Woodlawn Tree and Landscape is one of them — cutting, edging along the sidewalk slabs, trimming around fence posts and hydrants, keeping the beds mulched and the shrubs in shape. Under the old maples the grass grows thin and gets its own treatment: a higher cut and a careful hand. Cleanups come around twice a year to reset everything at once. By noon the block is quiet again and the lawns look level and green and squared away.