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Life Sciences Commons

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Plant Sciences

Selected Works

John E. Sawyer

2016

Active canopy sensors

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

Quantifying Corn N Deficiency And Application Rate With Active Canopy Sensors, Daniel W. Barker, John E. Sawyer Jul 2016

Quantifying Corn N Deficiency And Application Rate With Active Canopy Sensors, Daniel W. Barker, John E. Sawyer

John E. Sawyer

Precision agriculture technologies are an integral part of many operations in Iowa corn production. Active canopy sensors have been developed as a tool to determine plant N stress deficiency and provide on-the-go decisions for implementing variable rate N application. The objectives of this study were to assess N deficiency stress levels at the mid-vegetative corn growth stages with active canopy sensors, calibrate active sensors and associated canopy indices, and develop N rate algorithms that can be used to determine variable rate N fertilization.


Active Sensor Strategies For In-Season Application Of Urea In Corn, Daniel W. Barker, John E. Sawyer Jul 2016

Active Sensor Strategies For In-Season Application Of Urea In Corn, Daniel W. Barker, John E. Sawyer

John E. Sawyer

Addition of N fertilizer during the midvegetative corn (Zea Mays L.) stage is being used in Iowa to protect yield potential. The objective of this experiment was to compare pre-plant and in-season N application strategies, and evaluate N use efficiency and grain yield of sensor-based N rate application.