In Saxonville the Sudbury River drops over the old dam and the sound of it carries up the hill past the mill brick, steady as a fan left running. C.L.A landscaping services mows the neighborhoods along that river bend, holding the cut even where the ground rolls and the roots of the big silver maples push up under the turf. Trimming runs along the granite and the chain-link; clippings go with the truck rather than into the beds. Twice a year the yards get their cleanups — April to open them up, November to take the leaf off before the snow. It is week-in, week-out maintenance, and the reward is a lawn that never looks like it is catching up.