Fog lies low on Bass River most summer mornings, and it lifts just about the time the first mower comes off the trailer. Alef Santos Landscaping works Yarmouth's sandy ground — soil that drains fast, jumps after rain, and asks for a steady weekly hand. The work is mowing, string trimming, edging the walks, and keeping mulch beds ahead of whatever wants to move into them. There's a plain pleasure in the last pass, when the stripes run straight toward the water and the driveway edge is cut clean. Between salt air and pitch pine, a South Yarmouth lawn earns its green, and holding it there is the whole job.