On a June evening in South Dennis the fireflies come up out of the cedar swamp and drift over the lawns like slow sparks. JM Home & Yard mows this stretch of Dennis Township in the cooler hours, working yards ringed by pine and holly where the soil is more sand than dirt. Grass out here rewards patience — a proper cutting height, a sharp blade, a trim line where the lawn gives way to the woods. The result is a yard that reads as tended without looking fussy, which suits these roads exactly. Then the mower goes quiet and the crickets take the field.