v1.2 (2026-06-10) · CDFA Fertilizer Research and Education Program (FREP) + UC Davis Nutrient Management (Geisseler lab) California Crop Fertilization Guidelines. Component anchors: UC ANR Publication 8292 — Meyer, R.D., Marcum, D.B., Orloff, S.B., Schmierer, J.L. (2007). Alfalfa Fertilization Strategies. Ch. 6 in Summers, C.G. & Putnam, D.H. (eds.), Irrigated Alfalfa Management in Mediterranean and Desert Zones. UC ANR Publication 7228 — Hartz, T.K., Miyao, G., Mickler, J., Lestrange, M., Stoddard, S., Nuñez, J., Aegerter, B. (2008). Processing Tomato Production in California. CDFA-FREP Almond Nitrogen Uptake and Partitioning (Brown lab, UC Davis). CDFA-FREP Wheat (Ottman / Muñoz-Carpena et al.) + the UC Davis Nitrogen Fertilizer Management Tool for California Wheat (smallgrain-n-management.plantsciences.ucdavis.edu). UA Acala-cotton N research, Hutmacher & Roberts (2004, Agronomy J. 96:48 + Scientific World J. 2001), commonly cited in UC cotton N recommendations.
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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