There is an hour in early summer when White Park turns gold at the edges, the ball fields empty out slowly, and Concord smells like cut grass all the way down the hill. Dana Mercier mows to that standard — the even pass, the clean line where turf meets walkway, the corners nobody else bothers to reach. Grass here comes on fast after a wet spring and turns stubborn through August, so much of it is simply showing up on the same day, week after week. A yard kept that way stops being a chore and turns into somewhere you sit. It is lawn care done patiently in one city, one street at a time.