Spent Lime Delivers Results in Beet Fields

In an ongoing quest to improve production in sugarbeet fields, Sidney Sugars and a small group of cooperators have been testing spent lime on fields in the factory growing area. The lime is part of the process of making sugar. It starts out as calcium carbonate limestone, is heated up in the lime kiln where it separates into calcium oxide and carbon dioxide, then hot water is rushed over the calcium oxide to create a milk of lime which is injected into the sugar purification process. It attaches to impurities in the juice and is recombined with carbon dioxide to bring it back to its original composition of calcium carbonate which then is separated off. In 2012, lime presses were first used so that the spent lime is now being moved with less water and hauled off in trucks to stockpile.

Testing in other areas of the country showed positive impacts of spreading the spent lime on fields to help control disease. In 2013, the factory started looking for cooperators who were wiling to experiment on test fields. Four cooperators with five fields targeted eight to ten tons per acre. Half the field had lime, half did not.

In the four growing seasons since then, each year has seen better and better results according to Sidney Sugars agriculturalist Vanessa Pooch. The initial reason for the lime testing was to stop the disease aphanomyces; then it was to see what else it could do. Results show improved soil tilth and drainage with no detrimental effects. “You can actually see the line going down the middle of the field, and see the difference in soil health,” Pooch said. Besides the disease suppression, improved drainage results are another benefit, especially in a wet spring, or where water normally sits after rain or irrigating. The micronutrients that come with the lime are also beneficial. One grower who helped pull root samples could tell the difference immediately, seeing a healthier root which logic indicates a healthier plant.

Three of the four original growers continue to conduct the trail plots. A manure spreader has been used, but a wider fan spreader would be ideal. Pooch said there is a large interest from farmers in western North Dakota for use on non-irrigated land, not for disease suppression, but for soil tilth.

“I wish more people would create their own trials, even if it’s a small portion of the field,” Pooch said. “The lime is free and the results are pretty amazing.”