Eight cultivation programs with several equipment combinations were compared with each other and with an atrazine plus pendimethalin herbicide program with and without supplemental cultivation from 1992 to 1994. In two of the three years, cultivation with a rotary hoe or tine weeder reduced weed seedling density by 39 to 74%. Tine weeding was more effective than rotary hoeing in 1992. Rotary hoeing or tine weeding reduced corn populations by an average of 6%. Weed control by different types of inter-row cultivators varied little, except that an in-row cultivator provided better control than a rolling cultivator in two years and better control than a shovel cultivator in one year. Weeds establishing from seeds were better controlled by herbicides in all three years, but weeds establishing from roots, rhizomes, and tubers were controlled as well or better by cultivation. Weed control was sometimes better using herbicides plus cultivation than with herbicides alone, but the combination damaged the crop in two of the three years. Cost of mechanical treatments which combined inter-row cultivation with rotary hoeing or tine weeding differed from that for the herbicide treatment by less than 2%. Yields of the best mechanical treatment and the herbicide treatment were nearly equal in all years, but the best mechanical regime varied between years. Consequently, mean net return was moderately higher for the herbicide treatment.