Involves keeping normally cultivated land free of vegetation throughout one growing season by cultivating (plowing, discing, etc.) and/or applying chemicals to destroy weeds, insects and soil-borne diseases and allow a buildup of soil moisture reserves for the next crop year. Includes chemfallow, tillage, and/or a combination of chemical and tillage weed control on the same land. Part of the crop rotation system in Western Canada. Rarely found in Eastern Canada.