Do improved planting conditions following shallow vertical tillage result in higher crop yields? “Fine-textured soils and early planting are the two conditions where shallow vertical tillage may provide a yield benefit, compared to no-till,” says Mike Staton, Michigan State University Extension soybean agronomist,” in reference to studies from Michigan, Indiana and Canada.
1. Michigan yield data using vertical tillage
2010 and 2011 studies at five sites compared soybean yields with a Case Turbo Disk to no-till yields. At one site, yields with the Case Turbo Disk were about 3.6 bu./acre higher than no-till yields. But when all the trials were combined, there was no significant yield advantage for shallow vertical tillage. In another Michigan study at the Center for Excellence in 2011, five tillage treatments were compared: in-line ripper, disk ripper, strip tillage, shallow vertical tillage and no-till. There were no significant differences in soybean yields for tillage treatments.
2. Minnesota yield data using vertical tillage
Residue coverage was significantly higher for fall strip-till compared to other tillage treatments. Corn yields were higher in 2010 with the Salford RTS than with the chisel plow system. Corn yields in 2011 were not affected by tillage treatment.
3. Minnesota yield data using vertical tillage
2010 and 2011 trials at three sites compared strip-till, fall chisel plow plus spring cultivation, no-till and one or two passes of a Salford RTS or Summers Super Coulter shallow vertical tillage tool. Corn and soybean yields did not vary significantly by tillage treatment.
4. Indiana yield data using vertical tillage
trials on clay loam soils from 2004 to 2006 compared corn yields after one or two spring passes with a Great Plains Turbo Till to corn yields after strip-till, spring field cultivator, chisel plow plus field cultivator and no-till. A single pass of the Turbo Till after soybeans produced corn yields similar to spring field cultivation, while maintaining 10% more residue cover. A second pass of the Turbo Till did not increase corn yields.
5. Ontario, Canada, yield data using vertical tillage
A 40-site study from 2003 to 2005 found that a single spring pass with a Salford RTS increased soybean yields by less than 2 bu./acre compared to no-till. But on about 20% of the sites, the vertical tillage tool boosted yields by 3-5.5 bu./acre, a significant increase. The responsive sites were clay soils (slower to dry out in the spring).
6. Wisconsin vertical tillage data
The effects of shallow vertical tillage on soil disturbance and residue cover varied significantly, depending on soil type, machine characteristics and operating depth, according to a 2010 study by the University of Wisconsin. Sandier soils, more aggressive blades, and deeper operation all resulted in more soil disturbance and less surface residue.