December 17, 2020
- Tillage systems and operations have evolved over the years to meet specific production and/or environmental objectives.
- Considerations such as soil and water conservation, input costs, labor efficiency, timing of tillage, crop rotation, soil health, short- and long-term land usage, crop nutrient management, and pest management drive tillage decisions on farms.
- With improvements in tillage implements and herbicide technologies, farmers use an array of tillage options, ranging from conventional tillage to minimum tillage to no-till.
- Many farms do not use a single tillage system across the farm. Instead, a different tillage type is often deployed to meet the productivity requirement of each field and is in use for several years.
- It is necessary to periodically evaluate the continued suitability of tillage systems.
- The objective of this trial was to evaluate soybean productivity as impacted by three different tillage systems.
RESEARCH SITE DETAILS
- A 2.9 maturity group (MG) soybean variety was used for the trial.
- Trial was carried out in 15 ft x 500 ft plots, with 30-inch row spacing and four replications.
- The conventional tillage system consisted of disking followed by a soil finishing pass. The soil finisher implements comprised of a disk gang, a cultivator, and tine harrow units.
- The strip tillage system consisted of Vulcan Equipment’s ZoneMaster® Strip-Till unit comprised of
- row cleaners,
- no-till coulters that penetrated 2 to 3 inches deep and 7 inches wide, and
- rolling basket to break large soil clumps and smooth the soil before planting.
- All tillage operations were carried out in the spring.
- Weed management and nitrogen rate were the same across tillage systems
- Results from similar trials carried out in 2018 and 2019 are also provided.
UNDERSTANDING THE RESULTS
Figure 1. Soybean yield response to three tillage systems over a three-year period in central Iowa. Yield average represents the average performance of each tillage system over the three-year period.
- The average yields in 2020 were nearly the same for conventional tillage and no-till but 3 to4 bu/acre greater in the strip-till system.
- Plant density observations before harvest (harvest population) were not significant between the systems. The densities were 124,400; 124,000; and 123,800 plants/acre for conventional tillage, no-till and strip-till, respectively.
- Grain moisture content after harvest was nearly the same, approximately 11 percent, for all tillage systems.
- Overall, there weren’t many agronomic differences between the tillage systems over the three-year period.
- Crop yield response to tillage is site-specific and often impacted by environmental factors, soil type and drainage, and the cropping sequence. Several years of research are needed to truly determine the productivity of tillage systems.
- This trial suggests tillage system type is not a major factor in soybean production at the trial location. To save on production cost; however, no-till could be recommended if an efficient weed management strategy (such as chemical control) is available.
- Generally, the right tillage type provides the best economic returns while ensuring better environmental stewardship.