Dick and Sharon Thompson's “Problem Child”: A Decision Case in Sustainable Agriculture

In December of 1989, Dick Thompson was wondering what to do about the K deficiency problem that had persisted in his ridge‐tilled corn ( Zea mays L.). He and his wife, Sharon, owned and operated a 121‐ha (300‐acre) crop and livestock farm near Boone, IA. From 1967 until 1986 they had farmed organically. By 1986, however, K deficiency in their corn had become so serious that they felt they either had to use chemical K or “go broke.” Soil K levels were high. “Potassium has become such a problem for us, that we refer to it as our ‘problem child’,” said Thompson. The case has 12 exhibits, which include Thompson's own illustrated notes that trace his struggles with K in a variety of ways. His notes include the history of manure management, the nutrient status of his crops and soils, fertilizer experiments conducted on the farm, plus results and reports of farmers and scientists from Iowa, neighboring states, and Canada. After reviewing and considering all these factors, Thompson still wondered why the K stress persisted and what he should do about it. The case focuses on this decision. The decision requires consideration of the issue of organic vs. chemical farming, plus the validity of soil testing philosophies and associated fertilizer recommendations common to Thompson's location and time. The decision also requires an evaluation of Thompson's ridge‐tillage as well as manure/nutrient‐management systems. Objectives of the case are for students to analyze and discuss these issues and to propose and defend a course of action for Thompson regarding his K fertility program. The case has been used successfully in a senior‐level integrative course in animal/plant systems.