Morning fog lifts off the Merrimack near the Chain Bridge and sits in the low fields along the road toward West Newbury until the sun climbs high enough to burn it off. Walker Agro works that ground and the yards back in Newburyport, mowing on a steady rotation, trimming what the deck can't reach, and cutting edges where grass meets gravel or asphalt. Cleanups come twice — once when spring finally dries the ground out, once when the leaves are down and the beds need clearing. Grass near the river grows hard and fast in June and slows almost to nothing by August, so the schedule bends to the weather rather than the calendar. What's left behind is a lawn that looks even from any angle you come at it.