The new formula for computing the corn suitability rating of ag land should be ready by Jan. 1, according to Kelvin Leibold, an Iowa State University Extension farm management specialist. However, he added, "there is more than one version floating around out there, but there should be just one by the end of the year."
Leibold was speaking to ag lenders and commodity brokers at the the annual Pro Ag Outlook meeting at the Webster County Extension office.
Leibold said when the new formula for CSR 2 was released earlier this year. "Initially I thought it might affect CSR ratings by 1 percent," Leibold said.
"But now I think it might be bigger than that."
The original CSR formula, issued in the 1940s, was designed to provide a relative ranking of all soils mapped in Iowa based on their potential to be used in row-crop production. The initial formula, he said, used 11 factors to determine the value.
It hasn't changed, until now.
CSR 2 will be based on just seven factors which are:
The taxonomic subgroup class of the soils.
The particle size of the soil class.
Field conditions of a particular soil class.
Water-holding capacity of the series.
Soil depth and tolerable rate of erosion factor.
Expert judgment as a correction factor.
Acceptance of the ratings will depend, he said, on how the changes are perceived by land owners.
He used one unidentified Iowa farm showing that its historical CSR value was at 67. The new formula will drop that same farm to 58.
"The land didn't change," Leibold said, only the way the rating was figured. However, someone who just purchased the farm with its rating at 68, has suddenly paid more per CSR point, once the new formula dropped the land's rating to 58.
"That purchaser probably isn't going to be too happy about that," Leibold said.
Leibold said CSR2 is designed "to fine-tune productivity values that we think are out there."