Spring reaches Sharon by way of the marsh at the Audubon Center — peepers first, then the red-wings, then a green that climbs the hillsides toward Indian Mountain over about two weeks. Swaller's Lawn Care starts its year in that rush, when everything that made it through the winter decides to grow on the same Tuesday. The routine is mowing, trimming and holding lawns even through the long light of the northwest hills, with a rake-out of whatever winter left behind. There is real satisfaction in the first cut of the year: shaggy going in, striped and settled coming out, a yard that suddenly looks like summer's plan. After that it becomes a rhythm, week by week, until the leaves start down again.