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Soil Test Conversion Tools

Online Soil Test Conversion Tool

Warning and disclaimer: This program converts soil test results from Brookside Laboratories Inc. (Mehlich-3 P, K, Ca, Mg), Spectrum Analytic Inc. (Mehlich-3 P, K, Ca, and Mg and Morgan P, K, Ca, and Mg), A&L Laboratories Inc. (Mehlich-3 P, K, Ca, Mg and Modified Morgan P), and the soil testing laboratories from the University of New Hampshire (Mehlich-3 P, K, Ca and Mg), University of Massachusetts (Morgan P, K, Ca, and Mg) and the Universities of Vermont and Maine (Modified Morgan P, K, Ca, Mg) to Cornell University Morgan Equivalents. Phosphorus conversions from Mehlich-3 data require measured values for soil pH, Mehlich-3 P, Ca, and Al. For each test, the range of valid input data is given by a minimum value (min) and a maximum value (max). Also given are the correlation coefficients (r2) for each of the conversion models. The larger the (r2), the more reliable the conversion. Models were derived using New York soils. There is uncertainty involved with each of the conversions and we now know there is seasonality in the conversions with the most reliable conversions obtained when samples are taken after harvest and before manure application. The user assumes all risk and it is recommended to submit samples for the Cornell Morgan test to check on the accuracy of the conversion models for your farm or the farm you work with. It is also recommended to take 3 subsamples per acre if you use conversion models to derive Cornell Morgan soil test equivalents. For questions, contact Q.M. Ketterings ( Equations were last updated 8/30/2003.

Choose the soil extraction method:


Modified Morgan