Updating Soil-Based Yield and Productivity Data in Ohio.

Agricultural real estate taxes are assessed in the state of Ohio using the Current Agricultural Use Value (CAUV) program, which allows farmers to have their parcels taxed according to agricultural value, rather than full market value. Land values are assessed based on soil productivity and yield potential, realizing that a farm with more productive soils has a higher yield potential and therefore greater real estate value. The 3080 different soil map units found in Ohio have been divided into six typical cropping patterns for the purpose of calculating tax rates. In order to have a fair tax assessment system, it is necessary to have accurate crop yield predictions for each soil in Ohio as well a reliable and transparent method for rating soil productivity. The goal of this study is to use existing soil and climate data to create a reliable and transparent system for generating yield and productivity data for Ohio soils. Crop models are a well tested and generally accepted method for evaluating crop yield potential. Because Ohio tax rates are based soil, it is important to use a crop model that fully incorporates the soil properties most responsible for yield potential. In this study, the DSSAT crop modeling software was used to predict yield values for a number of soil series in Ohio. Climate, soil, and management data were inputs in the model. Soil data was compiled on a soil series basis and management was assessed at an “average” level. Soil productivity and yield potential were then compiled on a soil map unit basis using estimated map composition.