Boxborough still keeps its stone walls, and in June the light comes down through the oaks in pieces, across the fields at Flerra Meadows and the lawns beyond them. Acorn Tree & Landscaping inc. works those yards — mowing on a weekly line, edging where lawn meets gravel drive, trimming close to wall and post, mulching beds before the heat sets in. Country lots do not forgive a rushed pass; grass grows unevenly under trees and edges wander if you let them. Winter litter gets cleared once the ground firms up, and the leaves get taken out in November. A wide green yard, cut even, is most of what a Boxborough summer asks for.