In a 17-year Nebraska study, researchers found that conservation tillage gave higher irrigated corn yields and profits than tilled plantings. The average yield increase was 4 bushels per acre, while the three conservation tillage treatments resulted in $8 to $16 per acre less tillage costs than the conventional disc tillage treatment. The conservation tillage treatments were ridge-till, rotary-till and slot-plant, while tilled treatments consisted of chisel, disc or lister operations for the furrow-irrigated continuous corn plantings.
Higher yields and reduced costs help offset the additional herbicide costs involved with conservation tillage. In addition, there was less stalk rot and residual nitrate nitrogen in all three conservation tillage treatments.
—Journal of Production Agriculture, Volume 12:269-275 (1999).
Many no-till farmers in the Corn Belt apply starter fertilizers containing phosphorus and potassium to their no-till corn with generally positive results. However, very little research work has been done on evaluating the effect on growth, uptake and yields of applying phosphorus and potassium separately in starter treatments.
In a comprehensive study on research centers and farms from 1994 to 1996, Iowa State University researchers found that positive effects on early growth and/or uptake may not correlate with yield increases. For example, even though the early growth of no-till corn was enhanced with shallow banding (2 inches) and deep banding (6 inches) applications of phosphorus, there were not significant yield increases compared to broadcast…