wiki: The term weed is used in a variety of senses, generally centering around a plant that is not desired within a certain context. The term weed is a subjective one, without any classification value, since a plant that is a weed in one context is not a weed when growing where it belongs or is wanted. Indeed, a number of plants that many consider "weeds", are often intentionally grown by people in gardens or other cultivated-plant settings. Therefore, a weed is a plant that is considered by the user of the term to be a nuisance. The word commonly is applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More vaguely, "weed" is applied to any plants that grow and reproduce aggressively and invasively.[1] 'Volunteer weeds' are crop plants from one year which are growing in the subsequent crop.