There is a week in November when the sky over the airfield off Christian Street goes wide and hard-edged, the last leaves let go, and the town changes trades. Before then it is grass — mowing through the long green weeks, trimming, edging, hauling the fall off the lawns. After, it is snow: driveways plowed open, walks cleared, salt and sand on the steep spots that never catch much sun. Serving the same properties on both sides of that week teaches a town's small geography — the culvert lip, the shaded curve, the corner where wind stacks snow in exactly the same place every time. Oxford, hilly and half-wooded, gives plenty to learn, and the learning shows up in how fast a drive gets opened.