County Weighted Average CSR2
Author: Bradley Miller
This map displays the weighted mean Corn Suitability Rating 2 (CSR2) values by county across Iowa. CSR2 is a standardized index (0–100) representing the inherent productivity potential of soils for row crop production. County-level means were calculated using NRCS acreage data and CSR2 values from the Iowa Soil Properties and Interpretations Database (ISPAID), allowing for a broad comparison of soil productivity across regions.
Right-click image file to save.
Source:
Prepared by Aaron Sassman and C. Lee Burras
Department of Agronomy
Iowa State University
Ames, IA 50011
Interpretation:
The map highlights spatial differences in average soil productivity, with northwest Iowa counties such as O’Brien, Cherokee, and Grundy ranking among the highest. Southern and southeastern counties tend to have lower mean CSR2 values, reflecting more variable terrain, lower inherent fertility, or greater erosion risk.
Resolution:
County-level aggregation; displayed as a statewide static image
Suggested Use:
Valuable for land valuation, regional crop planning, and assessing agricultural productivity potential. Can guide resource allocation, farmland investment, and conservation prioritization at the county scale.
References:
Calculated from NRCS acreages and CSR2 values contained in ISPAID (Iowa Soil Properties and Interpretations Database) version 8.1 as of May 2017.