April along the Salisbury Point Ghost Trail smells like thawed mud and river water, and the first green shows on the banks of the Merrimack well before anybody's mower is out of the shed. Riverfront Landscape Co opens the season with the cleanups — winter sand raked out, beds cut back, the lawn cleared of everything the storms left behind — then carries on into weekly mowing, trimming, edging, mulch, shrub work, feeding and overseeding. Yards this close to the water hold their damp late into spring, so the first cuts are timed to the ground rather than the calendar. By the middle of May the turf has come in thick and the lines run clean down to the fence. From then until the leaves let go, it is a matter of showing up the same day each week and leaving the place better than it was.