The
Iowa Corn Suitability Rating 2 or
CSR2, is a revised soil rating system for Iowa Soils from the CSR values.
The CSR2 was developed by C. Lee Burras of the Department of Agronomy at Iowa State University.
According to Burras, “Advances in soil-mapping techniques and the adoption of the national soil classification system during the past 50 years provides improved methods for calculating the CSR when compared to its original formula.”
What is the CSR2?
CSR 2 is an updated index that takes the core concepts and calculations of the CSR Rating system and changes them to support a better defined and easily calculated formula to determine a soil’s productivity value. CSR 2 has taken a more data driven-approach when coming up with values instead of relying on a more fluid judgment and experience system of ratings that the original CSR had. (Hertz) The CSR 2 does not include a climate factor which was included in the original CSR evaluations. (Jensen)
CSR2 uses six parameters that result in the best soils being rated at 100 points. (Jensen 2013)
Formula for the
CSR2 =S-M-F-D +/- EJS = Taxonomic Subgroup class of the soil series
M = family Particle Size Class
F = Field conditions of a particular SMU (Soil Map Unit)
W = water holding capacity
D = Soil depth & Erosion factor T
EJ = Expert Judgement Correction Factor
Is there an impact on Iowa Farmland Owners?¶
The updated Rating system will impact each landowner differently based on if their soil values have increased or decreased. If the CSR2 value is lower then the CSR value was, then the value of the land may be impacted in that way as well. The inverse is true if the CSR2 value is higher than the original CSR value. It will be important for farmland owners to be conscious of both CSR and CSR2 values for their land to be able to recognize the difference. Mr. Jim Jenson states that if your land has a typical makeup within the county, then the value should follow the rest of the county. But if you have unique soils within your land, then the values may change independent from the typical county soils. (Jensen)
Where can I find the CSR and CSR2 Soil Ratings?CSR, CSR2 and Soil Mapping SourcesHow do I change the soils map back to see CSR values?
Since with each update to the soil database more and more soils types are being reclassified. The original CSR values will not appear within the Soil Map by default. In order to view the CSR data in these situations, a previous Soils Version needs to be used. See:
Soils Map History & Version
References:
Burras, L. (2013, May 23). Iowa State University Updates Method for Rating Soil Productivity. Retrieved from
https://www.cals.iastate.edu/news/releases/iowa-state-university-updates-method-rating-soil-productivityHertz Farm Management. (14, May 1). CSR andCSR2 - An Explaination. Retrieved from
http://www.hertz.ag/2014 Hertz CSR and CSR2.pdf
Iowa State University.(2013, May). Corn Suitability Rating (CSR) Background and Update. Retrieved from
http://www.extension.iastate.edu/page/sites/www.extension.iastate.edu/files/page/CSR2 FAQ Final.pdfJensen, J. (2013, September). CSR gets a makeover in forming the new CSR2 Productivity Index. Retrieved from
http://www.extension.iastate.edu/agdm/articles/others/JenSept13.htmlSee Also: