Stone walls run through the woods all over Winthrop, laid up back when the ground between here and Cobbosseecontee was pasture instead of pine. Folsom Landscape Fabrications works the lawns among them — mowing, edging, trimming close to the stone, mulching beds, clearing brush and leaves as the year turns. September is the month it all looks best: the grass deep green again after the August heat, the low sun raking across the wall lines. The cleanups come next, leaf by leaf, until the yards are bare and ready. It is steady, visible work, and a Winthrop yard shows it.