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Quantifying Corn N Deficiency And Application Rate With Active Canopy Sensors, Daniel W. Barker, John E. Sawyer
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.
Post Applied Urea+Agrotain To V10 Corn Field Scale Strip Demonstrations, Daniel W. Barker, John E. Sawyer
Post Applied Urea+Agrotain To V10 Corn Field Scale Strip Demonstrations, Daniel W. Barker, John E. Sawyer
John E. Sawyer
The objectives are to apply N fertilizer when corn rapidly accumulates N and dry matter during the mid-vegetative growth stages and utilize active sensors as a remote sensing method of applying VRT nitrogen.
Evaluation Of Optical Canopy Sensors For In-Season N Rate Management In Corn, Daniel W. Barker, John E. Sawyer
Evaluation Of Optical Canopy Sensors For In-Season N Rate Management In Corn, Daniel W. Barker, John E. Sawyer
John E. Sawyer
Optical canopy sensors are an emerging technology that can serve as a useful in-season N fertilizer management tool for corn (Zea mays L.) production. The sensors provide an estimate of plant biomass and N status at the time of sensing. These growth parameters can be used to make in-season N rate adjustments and variable rate N applications. Currently, a robust and accurate algorithm to determine the appropriate N rate based on canopy sensing is need in order to improve the effectiveness of active sensors in production fields. The objective of this study is to determine the ability of optical canopy …
Do Active Canopy Sensors Measure Biomass Or Chlorophyll In Corn?, Matthew Meade, Daniel W. Barker, John E. Sawyer
Do Active Canopy Sensors Measure Biomass Or Chlorophyll In Corn?, Matthew Meade, Daniel W. Barker, John E. Sawyer
John E. Sawyer
Vegetative indices from canopy sensors are currently being used as a tool to measure N deficiency in corn (Zea Mays L.). Symptoms of N deficiency include stunted growth (reduced biomass) and yellowing (reduced chlorophyll). It is unclear which sensor index is most useful. The objective was to determine if canopy sensor indices (NDVI and CHL) measure plant biomass or plant chlorophyll.
Corn Residue Harvesting Effects On Yield Response To N Fertilization, Jose L. Pantoja, John E. Sawyer, Daniel W. Barker, Mahdi Al-Kaisi
Corn Residue Harvesting Effects On Yield Response To N Fertilization, Jose L. Pantoja, John E. Sawyer, Daniel W. Barker, Mahdi Al-Kaisi
John E. Sawyer
Producers have many choices of diverse tillage practices for their corn (Zea mays L.) production systems. However, no-till has become an important soil management practice to help reduce water and wind erosion, as well as nutrient runoff, while conserving soil moisture for crop use. No-till systems also help farmers by saving labor and time, as well as reducing farm costs due to less equipment and fuel consumption. Nevertheless, no-till production is typically more successful and has higher crop yield on moderately to well drained medium-textured soils (Bitzer, 1998), compared to soils with poor internal drainage and high clay.
Corn Residue Harvesting Effects On Yield Response To N Fertilization, Jose L. Pantoja, John E. Sawyer, Daniel W. Barker, Mahdi Al-Kaisi
Corn Residue Harvesting Effects On Yield Response To N Fertilization, Jose L. Pantoja, John E. Sawyer, Daniel W. Barker, Mahdi Al-Kaisi
John E. Sawyer
Producers have many choices of diverse tillage practices for their corn (Zea mays L.) production systems. However, no-till has become an important soil management practice to help reduce water and wind erosion, as well as nutrient runoff, while conserving soil moisture for crop use. No-till systems also help farmers by saving labor and time, as well as reducing farm costs due to less equipment and fuel consumption. Nevertheless, no-till production is typically more successful and has higher crop yield on moderately to well drained medium-textured soils (Bitzer, 1998), compared to soils with poor internal drainage and high clay.
Active Sensor Strategies For In-Season Application Of Urea In Corn, Daniel W. Barker, John E. Sawyer
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.