v1.0 (2026-05-23) · South Dakota State University Fertilizer Recommendations Guide. SDSU operates through commercial labs (Ward, AgVise partnerships). Uses SMP buffer index; lab transitioned to Sikora in 2009 but applies the same SMP calibrations. Buffer test run when water pH < 5.6. Target pH 6.0 standard. Rates assume 90% CCE × 70% fineness ≈ 63% effective lime.
This source publishes a state method — its crop-specific rate tables are maintained in the extension bulletin rather than a fixed crop list, so Zone Forge doesn't claim a crop set here.
Lime calculator. Zone Forge computes this source's published lime rates in-app and cites the method.
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