SIDNEY, MT – An important two-year research project is underway at Montana State University's Eastern Ag Research Center in Sidney, Mont., comparing conventional till sugarbeet planting to no-till and strip-till planting methods. EARC researchers are also studying nitrogen management under these tillage practices. The study is being funded by a Western Sustainable Agriculture Research Education grant.
The ultimate goal of the project is to develop a sustainable conservation tillage system (strip till and no-till) for sugarbeet production with a package of optimized water and nitrogen management strategies that can be quickly adopted by growers in Montana and other regions. "Currently, most beet growers make four to five passes in the field in the spring," said Reza Keshavarz, EARC research associate, at field days. He is conducting the research project with Chengci Chen, cropping systems agronomist and EARC superintendent. Sugarbeets in Montana are often grown in a two- or three-year rotation alternating with spring grains, such as wheat or barley. In conventional tillage, producers make a few passes across a field for fertilizer application, discing, plowing or ripping, leveling, mulching and hilling - unless they are using conservation tillage. "When using intensive tillage, there can be issues with soil compaction, erosion, and water loss. The ground can dry out too quickly without the residue that no-till provides," Keshavarz said. With strip-till, farmers only till a narrow strip where the seed will be placed in later, and the rest of the soil will remain covered with the previous crop residue. Planting sugarbeets in the spring using strip-till methods is one way to minimize soil and wind erosion, but another way is to grow cover or companion crops in the fall. Another way to prevent soil and wind erosion would be to no-till beets, using a precision air seeder. A few producers in northeastern Montana are already planting sugarbeets no-till, but not many. These producers like that no-till saves fuel and labor with less passes, and that standing straw serves the same purpose as using a cover crop in the fall. The straw residue keeps the sun from crusting the ground, a problem in sugarbeet country in 2016, and protects the seedlings. It also saves soil moisture, and residue, chopped and spread evenly across the field, is helping to reduce transpiration. "Saving moisture is important when going from conventional till to no-till with a precision air seeder, but many producers have had problems with no-tilling sugarbeets," Keshavarz said. Straw management can be a challenge while shifting from conventional till to no-till and strip-till. This new research will evaluate that. "No-tilling can produce a better sugarbeet stand," he added. In the first year of study, the main plots of beets were seeded using conventional-till, strip-till and no-till. Nitrogen management was also looked at in other plots, using rates of zero, 50 pounds per acre, 100 pounds per acre and 150 pounds per acre, supplied with 46-0-0. Some first-year results: Tillage had a significant effect only on above ground biomass and plant stand. Above ground biomass and plant stand were higher in no-till compared to conventional tillage and strip tillage. No significant difference was found between tillage systems in terms of root yield, sucrose percent, sucrose yield and SLM. "This is highly important since no-till can provide economic benefits (lower cost, less labor, less fuel consumption) as well as ecosystem services (less soil erosion, soil compaction, etc.) and yet produce yields similar to conventional tillage," Keshavarz said. There was no significant response to increasing nitrogen rate. This shows that more efforts are needed to optimize nitrogen fertilization for beets under various tillage practices. The study will be repeated this year.