Alan Earl Olness, devoted husband, father, grandfather, and distinguished soil scientist, passed away from liver cancer on September 11, 2026, at the age of 84.
Alan was born on September 22, 1941, in Faribault County, Minnesota, to Albert and Arlette Olness. He married Valerie Keeling of Sheffield, England, on December 21, 1963, in Skyberg, Minnesota. Together, Alan and Valerie shared 62 years of marriage, travelled the world, and built a life on enduring love, devotion, and family. Valerie was his beloved soulmate and constant companion.
Alan is survived by Valerie; their four children, and five grandchildren. Allyson and her husband Todd Valnes, Iain and his wife, Leslie, their daughters Jordan and Taylor; Colin and his wife, Stephanie, their daughter Kennedy; and Erik and his wife, MinSook, their sons Colten and Cayden. He was preceded in death by his parents, Albert and Arlette, and his grandson, Logan (Colin and Stephanie).
Alan’s dedication to learning began at the University of Minnesota Morris, where he earned a bachelor’s degree in soil science, with a minor in mathematics, in 1963. He continued his education at the University of Minnesota Twin Cities, earning a master’s degree in 1967 and a doctorate in 1970. As an undergraduate, he was active in Delta Theta Sigma and Alpha Zeta, an agricultural honor society.
Alan devoted his professional life to helping people better understand the soil beneath their feet and to applying that knowledge for the benefit of farmers, agriculture, and the environment. As a soil scientist and lead scientist with the U.S. Department of Agriculture’s Agricultural Research Service, he conducted research at the North Central Soil Conservation Research Laboratory in Morris, Minnesota. His work focused especially on soil fertility, nitrogen availability, and the many interactions among soil, water, nutrients, crops, and farming practices.
A major theme of Alan’s research was nitrogen mineralization – the natural process through which soil microorganisms convert organic nitrogen into forms crops can use. He studied how efficiently crops used fertilizer and how soil moisture, manure, tillage, crop rotations, and the management of crop residues affected the timing and amount of nitrogen available to plants. His findings helped farmers make better nutrient-management decisions, improve yields, use fertilizer more efficiently, reduce unnecessary expense, and lessen the risk of nitrogen loss to the environment.
One of Alan’s most significant achievements was his leadership in developing the ARS Nitrogen Fertilizer Decision Aid, released in 1999. The computerized model used basic soil and weather information to estimate how much nitrogen would be released by soil microorganisms between planting and the time corn reached the side-dress or five-leaf stage. It combined that estimate with the nitrogen already present in the soil and calculated how much additional fertilizer was needed to reach an appropriate target level. It demonstrated how management choices could influence nitrogen release: leaving residue on the surface and reducing tillage could slow the process, while incorporating residue through tillage could accelerate it. USDA reporting indicated that the decision aid could improve nitrogen fertilizer-use efficiency by more than 10 percent compared with general application methods
Alan was also an inventor. Working with colleagues, he developed the Isopotential Available Ion Extractor, a reusable device designed to obtain a representative sample of ions available in soil or water. The method used ion-exchange materials to examine several elements and their relationships under conditions intended to better reflect their availability to plants. The extractor contributed to more meaningful evaluation of nutrients and other soil constituents and remains part of Alan’s scientific legacy.
His research extended beyond nitrogen to the relationship between soil organic carbon and plant-available water. Alan and his colleagues examined how increases in organic carbon could improve soil’s ability to hold water, providing a scientific basis for understanding the agricultural value of building and protecting soil organic matter. His work ultimately encompassed soil carbon and nitrogen sequestration, soil quality, and water-holding capacity – subjects that have become increasingly important to resilient and sustainable agriculture.
Alan also investigated vanadium, a naturally occurring element in agricultural soils that standard soil tests often overlooked. His research showed that vanadium could interfere with phosphorus uptake and disrupt the nutritional balance of plants, potentially reducing soybean yields even when ordinary phosphorus tests appeared adequate. He developed a method for measuring vanadium and evaluating its ratio to phosphorus and other nutrients, work that could help refine fertilizer recommendations and better explain unexpected crop responses.
Throughout his career, Alan combined scientific curiosity with a practical concern for farmers. Whether studying manure, soil moisture, crop residue, nitrogen availability, organic carbon, water retention, or the complex balance of ions in soil, he sought answers that could be translated into sound decisions in the field. His research helped advance the understanding that healthy, productive soil is a living and interconnected system.
Alan leaves a lasting legacy in the family he loved, the scientific knowledge he helped build, the tools he developed, and the agricultural practices his work helped improve. He will be remembered for his devotion to Valerie and their family, his keen and questioning mind, and a lifetime spent in service to science, agriculture, and the responsible care of the land.