v2.3 (2026-08-23) · University of Idaho Extension Fertilizer Guides (Northern and Southern Idaho series). Northern ID: CIS-453 Winter Wheat (Mahler, rev. Feb 2015) https://www.uidaho.edu/extension/publications/cis-0453 ; CIS-1101 Soft White Spring Wheat https://www.uidaho.edu/extension/publications/cis-1101 ; CIS-1012 Spring Canola https://www.uidaho.edu/extension/publications/cis-1012 ; CIS-1135 Oats https://www.uidaho.edu/extension/publications/cis-1135 . Southern ID: CIS-373 Irrigated Winter Wheat (Brown, Oct 2001) https://www.uidaho.edu/extension/publications/cis-0373 ; CIS-828 Irrigated Spring Wheat ; CIS-1082 Irrigated Winter Barley ; BUL-935 Sugar Beets ; BUL-970 Soil-Testing Procedures for Southern Idaho Soils (Rogers, Dari, Walsh 2020) https://www.uidaho.edu/extension/publications/bul-0970 . McFarland et al. 2020 SSSAJ Palouse buffer study: https://acsess.onlinelibrary.wiley.com/doi/10.1002/saj2.20111 .
State extension method. Zone Forge computes this source's supported nutrient rates in-app and cites the published method. Its published lime method is computed in-app too.
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