The Soil Fertility Lab has published a fact sheet reporting their results investigating the relationships between Mehlich-3, Bray P, and Ammonium Acetate soil test extractants in the Tri-State Region.
Summary of Findings
- Soil samples in Ohio and Indiana were collected from a diverse range of fields and analyzed for Mehlich-3, Bray-P, and ammonium acetate extractable nutrients for phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg).
- Mehlich-3 P values were highly related to, but 35 percent higher than Bray P values.
- Mehlich-3 K values were highly related to, but 14 percent higher than AA-K values.
- Mehlich-3 is a reliable extractant and will be the basis for updated fertilizer recommendations.
Full fact sheet can be found HERE