Late August, and the evenings at Rock Ridge Lake come on cool while the lawns still hold the whole day's heat. Mike K Services L.L.C. keeps the grass in Jefferson's lake neighborhoods on an even keel — mowing, string trimming, edging along walks and drives, clippings cleared off the pavement. Yards get dug out from under the winter in April and cleared of leaves again in November. Between the ledge outcrops and the tight lots, mowing up here is a game of angles more than acreage. A small yard cut well reads just as sharp as a big one.