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Jason Clark

Assistant Professor & SDSU Extension Soil Fertility Specialist


Berg Agricultural Hall 310
Agronomy, Horticulture & Plant Science-Box 2207A
University Station
Brookings, SD 57007

Soil fertility guidelines for South Dakota cropping systems

State & Regional Offices

SDSU Campus

Also by Jason Clark

a stretching field of green corn plants

Comparing Yield Goal and Maximum Return to Nitrogen Prediction Methods for Determining Corn Economic Optimal Nitrogen Rates

Fact sheet evaluating the accuracy of different corn nitrogen recommendation approaches with their advantages and disadvantages.

Dark green corn plants without any visual sign of nutrient deficiency symptoms.

Monitoring Corn Nutrient Deficiencies: The Traditional and Precision Ag Approach

To maximize growth and productivity, plants require 17 different nutrients.

an image of the cover of the SDSU Extension Fertilizer Recommendations Guide

SDSU Extension releases updated 2023 corn nitrogen fertilizer rate guidelines

March 27, 2023

South Dakota State University Extension has updated the corn nitrogen Fertilizer Recommendations Guide to reflect lowered rate recommendations.