Montana's land-grant extension publishes a method — not a one-size-fits-all rate. Live method: 1.5 × (target pH − current pH) for wheat, with MSU's incorporation condition called out on the result. Enter the required soil-test values in the free calculator for tons of CaCO₃-equivalent per acre, ECCE-adjusted, with the citation.
Central/northern Montana wheat country is acidifying. Eastern MT and irrigated valleys can still be alkaline.
Published source: Montana State University — Soil acidification rule (1.5 × ΔpH)
For Montana wheat country MSU publishes a simple rule: tons CaCO3/A = 1.5 × (target pH − current pH), with wheat evidence targeting pH 6.0. Surface-only lime does not move well in dryland soils — MSU says incorporate aglime into the root zone. Enter pH in the free Zone Forge lime calculator for tons of CaCO3-equivalent per acre, with the citation.
MSU Soil Fertility's published wheat-country rule is 1.5 × ΔpH (target 6.0 for the staged calculator crop). Aglime must be incorporated; surface application will not correct root-zone acidity. Source: Montana State University — Soil acidification rule (1.5 × ΔpH).
Zone Forge computes Montana lime from that state's published land-grant method (measured water pH and wheat target pH (MSU rule: 1.5 × ΔpH tons/ac); aglime must be incorporated into the root zone) — lime calculator, soil-test fertilizer, and full variable-rate prescriptions. See the science →