Everything on Shelter Island arrives by ferry, weather included, and it lands with salt on it. Liberty Lawn & Landscape works this ground on both sides of the year — mowing, trimming, edging and seasonal cleanups through the green months, plowing and shoveling and salting once the harbors go still and gray. Island lawns run right up against bay grass and the wood edge of Mashomack, so deciding where a lawn stops matters as much as how it is cut. In the off months, with the crowds gone and the light lying long and low over Dering Harbor, an open driveway counts for more than ever. It is a small place, and the work shows.