Building Soils for Better Crops, Third Edition

Summary and Sources

SARE Outreach
Fred Magdoff and Harold van Es | 2010 | 294 pages
PDF (6.8 MB)

This title is temporarily out of print. We expect to publish an updated edition in the spring/summer of 2021.


The preponderance of research indicates that there is no “ideal” ratio of cations held on the CEC with which farmers should try to bring their soils into conformity. It also indicates that the percent base saturation has no usefulness for farmers. Professor E. O. McLean (a former student of Albrecht) and coworkers at Ohio State University summed up their research on this issue in a 1983 article as follows: “We conclude from the results of all aspects of this study that in fertilizer and lime practice, emphasis should be placed on providing sufficient, but nonexcessive levels of each basic cation rather than attempting to adjust to a favorable basic cation saturation ratio which evidently does not exist, as others have also reported…”

And as Kopittke and Menzies put it in a 2007 article that reviewed the older as well as newer research: “Our examination of data from numerous studies (particularly those of Albrecht and Bear themselves) would suggest that, within the ranges commonly found in soils, the chemical, physical, and biological fertility of a soil is generally not influenced by the ratios of Ca, Mg, and K. The data do not support the claims of the BCSR, and continued promotion of the BCSR will result in the inefficient use of resources in agriculture . . .”

If you would like to delve into this issue in more detail, see the articles by McLean et al. (1983), Rehm (1994), and Kopittke and Menzies (2007) listed in “Sources” below.


Allen, E.R., G.V. Johnson, and L.G. Unruh. 1994. Current approaches to soil testing methods: Problems and solutions. In Soil Testing: Prospects for Improving Nutrient Recommendations, ed. J.L. Havlin et al., pp. 203–220. Madison, WI: Soil Science Society of America.

Cornell Cooperative Extension. 2000. Cornell Recommendations for Integrated Field Crop Production. Ithaca, NY: Cornell Cooperative Extension.

Hanlon, E., ed. 1998. Procedures Used by State Soil Testing Laboratories in the Southern Region of the United States. Southern Cooperative Series Bulletin No. 190, Revision B. Immokalee: University of Florida.

Herget, G.W., and E.J. Penas. 1993. New Nitrogen Recommendations for Corn. NebFacts NF 93-111. Lincoln: University of Nebraska Extension.

Jokela, B., F. Magdoff, R. Bartlett, S. Bosworth, and D. Ross. 1998. Nutrient Recommendations for Field Crops in Vermont. Brochure 1390. Burlington: University of Vermont Extension.

Kopittke, P.M., and N.W. Menzies. 2007. A review of the use of the basic cation saturation ratio and the “ideal” soil. Soil Science Society of America Journal 71: 259–265.

Laboski, C.A.M., J.E. Sawyer, D.T. Walters, L.G. Bundy, R.G. Hoeft, G.W. Randall, and T.W. Andraski. 2008. Evaluation of the Illinois Soil Nitrogen Test in the north central region of the United States. Agronomy Journal 100: 1070–1076.

McLean, E.O., R.C. Hartwig, D.J. Eckert, and G.B. Triplett. 1983. Basic cation saturation ratios as a basis for fertilizing and liming agronomic crops. II. Field studies. Agronomy Journal 75: 635–639.

Penas, E.J., and R.A. Wiese. 1987. Fertilizer Suggestions for Soybeans. NebGuide G87-859-A. Lincoln: University of Nebraska Cooperative Extension.

The Penn State Agronomy Guide. 2007–2008. University Station: Pennsylvania State University.

Recommended Chemical Soil Test Procedures for the North Central Region. 1998. North Central Regional Research Publication No. 221 (revised). Columbia: Missouri Agricultural Experiment Station SB1001.

Rehm, G. 1994. Soil Cation Ratios for Crop Production. North Central Regional Extension Publication 533. St. Paul: University of Minnesota Extension.

Rehm, G., M. Schmitt, and R. Munter. 1994. Fertilizer Recommendations for Agronomic Crops in Minnesota. BU-6240-E. St. Paul: University of Minnesota Extension.

SARE. How to Conduct Research on Your Farm or Ranch. 1999. Available online, along with other SARE bulletins.