DURING THE PAST 20 YEARS, North American farmers have been using increasing amounts of conservation tillage. This movement has resulted in about 30 percent of cropland currently being under some form of conservation tillage. Farmers indicate that their mails reasons for adopting conservation tillage are to reduce cost and increase net profits. Optimum tillage practices have become site-specific much like fertilizer and pesticide recommendations. Tillage and planting equipment is being designed to handle a broader range of field conditions. Capability to operate in and maintain surface residue, as well as integration of pesticide application, are important characteristics of conservation tillage machines. Most major machine types have been modified for conservation tillage. Combines have also been altered to provide more uniform straw distribution after harvest. Tractor design has been changed very little due to the shift to conservation tillage.