Some custom applicators and retailers are now offering strip tillage (ST) as an additional service in applying fall fertilizer. ST is becoming more popular with corn producers in our area of service and application acres are growing each year, particularly in the drier areas of the Great Plains. ST is also becoming more common throughout the major corn growing states, including IN, IL, IA, MO and others. The U of MN Extension service conducted 2 grower meetings this past July in Lamberton and Waseca and had over 600 in attendance.
Strip tillage has the best fit for corn producers who practice or want to practice minimum-till or modify their no-till systems. The erosion control benefits of no-till have the drawback of usually delayed planting in cool, wet soils with often times uneven crop emergence and stratification of non-mobile nutrients (P and K) in the top 1 – 2 inches of soil. Using ST techniques in the fall, these drawbacks can be overcome because the soil in the ST row is warmer and drier, similar to conventional-till soil temperatures and soil conditions and the P and K can be placed deeper in the soil. ST then results in earlier planting opportunities and better, more uniform stand establishment plus has the surface residue for wind and water erosion control and the soil water holding benefits associated with no-till. Two field operations are accomplished in one-pass. This saves the grower dollars in time, labor and fuel, as compared to a minimum or conventional- till system. In many cases the yields are at least equal to or better than conventional or no-till systems.
Strip tillage in the Upper Great Plains is most often done in the fall of the year with the application of fertilizer to a depth of about 4 – 8 inches deep. The distance between the ST rows is designed to match the producers’ corn planter, because in the spring, the planter will seed right on top of the ST row. The width of each ST row is generally 10-12 inches wide and is slightly raised to form a “berm” about 3 – 4 inches high. This berm will be warmer and drier in the spring than the area of untilled soil right next to the berm. This means planting earlier, better emergence and more uniform stands. One of the main problems with this ST system is getting the planter to stay on the ST row, but using GPS with auto-steer, this has become much easier. Planting can then be done 24 hours a day if necessary.
One of our topics for the upcoming AGVISE Fertility Seminars (Jan. 10, 11, 12, 2007) will be on strip-till research and will be presented by Anthony Bly, SDSU Research Associate (M.S. 1992). He has been working on fertility and tillage research projects since 1992 and should bring a very interesting perspective to this subject.