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Missouri algorithm: Design & objectives. Peter Scharf University of Missouri. Peter Scharf Newell Kitchen, Ken Sudduth, Glenn Davis, John Lory, Vicky Hubbard, Kent Shannon, Harlan Palm. On the way here, I saw a lot of money laying on the ground!!. Missouri Algorithm: Objectives.
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Missouri algorithm:Design & objectives Peter Scharf University of Missouri Peter Scharf Newell Kitchen, Ken Sudduth, Glenn Davis, John Lory, Vicky Hubbard, Kent Shannon, Harlan Palm
On the way here, I saw a lot of money laying on the ground!!
Missouri Algorithm: Objectives • Don’t leave money laying on the ground • Supply enough N to the crop to support full yield • Don’t apply N that the crop doesn’t need • Don’t let N escape from fields to water
Crop N need is variable • Twenty on-farm N rate experiments in Missouri, corn after soybean, no manure • Most profitable N rates were 109, 114, 175, 0, 90, 190, 244, 63, 119, 300, 0, 146, 146, 180, 52, 175, 112, 149, 136, 114 lb N/acre
N underapplied N overapplied Wasted $ Environmental risk Overapplication = leftover N in soil
Mouth of Mississippi River Huge algal bloom
Missouri algorithm design:Just an empirical relationship • John Lory and I: initial calibration with Cropscan • Newell Kitchen et al: more recent field-scale calibration of Greenseeker and Crop Circle • Multi-state (country) data from this group
Missouri Algorithm: Objectives, Set 2 • Deal with spatial variability in N need • Support producer, retailers, consultants in planned sidedress operations from V6 to V16 • Support producer, retailers, consultants in rescue N applications when previously applied N has been lost
Supporting producers in planned sidedress operations using sensors • 26 demo fields in 2007 ( ) • 61 demo fields 2004-2007 Nearly 30 demo fields 2008, including first cotton field
Controller runs ball valve to change fertilizer rate Computer in cab reads sensors, calculates N rate, directs controller sensors Color sensors can be used for sidedressing anhydrous…
Overall: +$13/ac to sensors On-farm sensor demos 2004-2007
Sensor Benefits: • Make sure enough N is applied • Avoid unneeded N application
N application to head-high corn N rate map June 20, 2007
129 bu/ac 149 bu/ac High-N reference area 115 175 175
Sensor Benefits: • Make sure enough N is applied • Avoid unneeded N application
Avg Bu/A 208.6 Fixed 214.1 208.0 208.5 206.6 206.6 211.6 205.4 Variable 215.4 212.1 204.2 212.4 215.5 204.9 206.6 210.2