Connecting Past with Present: Soil Fertility Insights from Historical Experiments

January 2024 | 26 min., 10 sec.
by Audrey Gamble
Auburn University

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​This presentation examines the Cullars rotation. Established in 1911, it is the oldest continuous soil fertility experiment in the South, and it demonstrates the effect of soil fertility management on cotton, corn, soybean, and wheat yields. Cash crop yields for corn are reviewed from 1911 to 2023 with focuses on the effects of specific fertility factors in given years. Two key lessons are offered at the end of the presentation: (1) Historic experiments offer a unique opportunity to quantify long-term effects of soil fertility issues, and (2) Soil fertility and soil conservation practices work together to improve soil health and sustainability.

About the Presenter

Audrey GambleAudrey Gamble is an assistant professor in the Department of Crop, Soil, and Environmental Sciences at Auburn University and an Extension soil scientist for the Alabama Cooperative Extension System. She received a PhD in soil chemistry from the University of Delaware and an MS degree in agronomy and soils from Auburn University. Her research and Extension programming focuses on 1) providing soil fertility recommendations for major row crops, including cotton, corn, peanuts, and soybean, and 2) evaluating soil conservation practices (cover cropping and conservation tillage) in row crop production systems. 

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