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Delaware — UD Cooperative Extension Soil Testing Program (Mehlich-3 / UD-FIV)

v1.5 (2026-08-24) · UD Cooperative Extension Fact Sheet AGR-Grain-Corn 'Grain Corn — Nutrient Recommendations — Agronomic Crops' (last updated 2019-07-01). UD Soil Testing Program: 'Interpreting Soil Phosphorus and Potassium Tests' (https://www.udel.edu/academics/colleges/canr/cooperative-extension/fact-sheets/interpreting-soil-phosphorus-and-potassium-tests/). UD Nutrient Management for Corn in Delaware: The Pre-Sidedress Nitrate Test fact sheet. Adams-Evans buffer pH method for lime — see coastal_plain_adams_evans for the shared Coastal Plain lime source (verbatim DE-anchored 67% ECCE basis).

State extension method Computes rates in-app
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Crops covered

AlfalfaBarleyCornCorn silageGrass / forageGrass hayOatsPastureRyeSorghumSorghum silageSoybeansWheat

Nutrient source for

DE

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What method does Delaware — UD Cooperative Extension Soil Testing Program (Mehlich-3 / UD-FIV) use?

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

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