Out toward the Moon River the water goes glassy in October, and an egret will stand in the shallows like it has all day. Thorn Lawn Service spends those cooler mornings mowing, trimming and edging Montgomery yards, then clearing cuttings and leaves off every walk before the truck moves on. Fall down here is less an ending than a change of tempo, the grass slowing, the light softening, the routine holding. A lawn cut at the right height in autumn goes into the short winter looking healthy rather than ragged. It is quiet work, and the results speak in clean margins and open, uncluttered lawns.