Soil survey versus crop production as a measure of soil productivity: Soil characteristics as predictors of corn and soybean yields, NCSS (National Cooperative Soil Survey) data base. Final report

Information has been assembled concerning land as a resource for farming and other endeavors. Major land resources areas (MLRAs) consist of geographically associated land resource units characterized by particular patterns of soil, climate, use and type of farming. The National Cooperative Soil Survey data base contains information concerned with crop yield and soil characteristics associated with MLRAs. Within MLRAs are various soils that have different chemical and physical properties such as soil pH, percent organic matter and texture, and that have different characteristics such as erosion and slope. A major objective of the project was to establish and evaluate a general, quantitative relationship between soil characteristics and yields for MLRAs in Iowa and Illinois. Statistical model building procedures were the methodology used in the evaluation and the test crops were corn and soybeans since these crops are widely produced in both states and on most soils.