Late October in Ayer turns the oaks along the Nashua River the color of old brass, and that is when H.M. Flagg Tree reads the canopy hardest — which limb has gone hollow over a Main Street roofline, which maple wants shaping before the first heavy wet snow comes down out of the Nashoba hills. They take down trees for homeowners, businesses, and the towns themselves, prune and trim what is worth keeping, and grind the stumps out until the ground is smooth enough to seed. Come winter the same trucks push snow off drives and lots before the mill-town streets have properly woken, and seasoned firewood goes out by the cord to houses that will burn it through February. There is a real satisfaction in the aftermath: a yard opened back up to the low winter light, a clean cut sixteen feet up that no one will ever notice, a clear apron of pavement steaming faintly at seven in the morning. It is work that leaves a place better lit, better drained, and easier to walk across.