The first real mow in Northfield usually lands in early May, once the ground firms up above the Winnipesaukee River and the grass has gotten ahead of itself. RBS Property Maintenance takes those yards on — up Arch Hill, along the flats near the bridges into Tilton — mowing, trimming, edging, mulching and clearing winter's grit out of the beds. Plow sand works its way into everything by April, and hauling it back out is half of what opening a season means. The payoff shows from the road: a lawn that looks intentional rather than accidental. In October the same care runs in reverse, leaves off and the yard put to bed.