> “Last season, a few pivots went over the 13-inch yearly average allotment.” Cullan is thankful the three growing seasons just before 2020 delivered better-than-average rainfalls. “Those years we only needed to use 2 to 3 inches of water on some fi elds throughout the growing season, which helps balance our fi ve-year average use.” Ogallala Aquifer Levels Declining Strategic dryland and irrigation management and precision irrigation technologies are helping growers adjust for drought conditions and related crop stress, but water levels in the Ogallala Aquifer remain a concern. The map below shows changes from the time before the aquifer was tapped to 2015. Lower Aquifer Levels In Nebraska and much of the western U.S., water use from aquifers is a growing concern. Overall, water demand has been pumping out gallons faster than rain and snowmelt can replenish them. Within 50 years, many regions could see freshwater supplies reduced by one-third, according to U.S. Forest Service projections. That’s a sobering trend, but it’s one Cullan and other Great Plains farmers and ranchers have been dealing with for years, as Ogallala Aquifer levels decline. One of the world’s largest freshwater aquifers, it lies under a 174,000-square-mile area stretching from southern South Dakota to western Texas and supplies water for almost 30% of the irrigated crops and livestock in the U.S. Retaining Soil Moisture Nebraska leads the nation in irrigation acres. While farmers there have always looked for ways to reduce water use and related costs, changing weather patterns and long-term climate predictions are driving more farm management decisions. Cullan has always focused on maximizing soil moisture in the cropping operation he runs with his cousin Tom Cullan. With about 60% of their acres in dryland production, a crop rotation that maximizes residue is a key Source: National Climate Assessment, 2018 8 WINTER 2021 CHSINC.COM