Frost in July is nothing unusual in Silverthorne, and neither is a lawn that shows the strain of it. High Altitude Repair Services works the ground at 8,700 feet, where thin air, cold nights and long winters leave turf patchy and matted by the time the snow finally quits — mowing it back into shape, trimming the ragged margins, raking out the pressed-flat thatch, and clearing off what the snowpack left. Under Ptarmigan Peak the properties run to slope and stone, and every yard keeps its own trouble spot. Bringing a beaten-up mountain lawn back to even green is slow, ordinary work. By midsummer that same yard reads as one solid sheet of color from the road.