A lawn is an area of soil-covered land planted with grasses or (rarely) other durable plants such as clover which are maintained at a short height with a lawnmower and used for aesthetic and recreational purposes. Common characteristics of a lawn are that it is composed only of grass species, it is subject to weed and pest control, it is subject to practices aimed at maintaining its green color (e.g., watering), and it is regularly mowed to ensure an acceptable length, although these characteristics are not binding as a definition. Lawns are used around houses, apartments, commercial buildings and offices. Many city parks also have large lawn areas. In recreational contexts, the specialised names turf, pitch, field or green may be used, depending on the sport and the continent.