Is it ensure, insure, or assure?
An area that is dominated by grass or grasslike vegetation. Moderately dry climatic conditions and seasonal disturbances, such as floods or fires, are generally conducive to the growth of grasses and prohibitive of that of trees and shrubs. Grasslands are found in tropical, subtropical, and temperate regions and typically occupy regions between forests and deserts.
area in which the vegetation is dominated by a nearly continuous cover of grasses. Grasslands occur in environments conducive to the growth of this plant cover but not to that of taller plants, particularly trees and shrubs. The factors preventing establishment of such taller, woody vegetation are varied