North Smithfield keeps its stone walls and its hayfields, and on a June evening the light comes down long and gold over Slatersville while the Branch River goes quiet under the trees. Twins Lawncare LLC mows in that light — cutting, trimming, edging and clearing away the clippings on lawns from the village greens out to the road-end places where the field starts again. A mown lawn out here has to sit right against wild ground, and the line between kept and unkept is most of the art of it. There is real pleasure in a yard that looks brushed rather than shorn, stripes running true to the stone wall. That's the standard, cut after cut, all summer long.