v2.3 (2026-06-10) · Koenig, R. (n.d.), 'Eastern Washington Nutrient Management Guide', WSU Extension EB1987E (https://s3-us-west-2.amazonaws.com/smallgrains.wsu.edu/uploads/2013/11/EB1987E.pdf). Marx, E.S., Hart, J., Stevens, R.G. (rev. Aug 1999), 'Soil Test Interpretation Guide', WSU/OSU Extension EC 1478 (https://s3.wp.wsu.edu/uploads/sites/2071/2014/04/ec1478-SoilTestInterpretationGuide.pdf). Antonangelo, J.A., Wieme, R., McFarland, C. (June 2025), 'FS398E Lime Requirement Estimates for the Inland Northwest', WSU Extension (https://wpcdn.web.wsu.edu/wp-ecommerce/uploads/sites/2/woocommerce_uploads/FS398E-uxhibg.pdf).
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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