Zone Forge reads your Montana soil test in Montana's own calibrated language — the critical levels and rate logic come straight from Montana State University Extension — EB161 Fertilizer Guidelines for Montana Crops, not a national average.
Per Montana State University Extension — EB161 Fertilizer Guidelines for Montana Crops — below the critical level, a yield response to the added nutrient is expected.
Published source: Montana State University Extension — EB161 Fertilizer Guidelines for Montana Crops
Montana State University Extension — EB161 Fertilizer Guidelines for Montana Crops. Zone Forge cites the publication on every recommendation.
Yes — the Montana soil-test recommendation calculator is free and needs no signup. Enter your lab values for source-cited P, K and lime guidance.
Zone Forge reads every Montana soil test in its own state's language, then builds source-cited fertilizer and lime recommendations and full variable-rate prescriptions. See the science →