Coverage · Source

Arizona — University of Arizona Cooperative Extension (Olsen-P calibration)

v1.2 (2026-06-21) · Ottman, M.J. (2020). Fertilizing Small Grains in Arizona. UA Cooperative Extension AZ1845. + Silvertooth, J.C. & Norton, E.R. (rev. 2011). Management of Fertilizer Nitrogen in Arizona Cotton Production. UA Cooperative Extension AZ1243. + UA Alfalfa Soil Management — Phosphorus / Potassium / Nitrogen sections (acis.cals.arizona.edu/agricultural-ipm/field-crop/alfalfa/soil-management).

State extension method Computes rates in-app
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Crops covered

AlfalfaBarleyCottonSmall grainsTriticaleWheat

Nutrient source for

AZ

Frequently asked

What method does Arizona — University of Arizona Cooperative Extension (Olsen-P calibration) use?

State extension method. Zone Forge computes this source's supported nutrient rates in-app and cites the published method.

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