Validating Post-Emergent N Application Algorithms for the GreenSeeker tm Optical Sensor in Cereals and Canola using UAN Solution. G. P. Lafond and W.E. May Indian Head Research Farm C.B. Holzapfel Indian Head Agricultural Research Foundation

ACKNOWLEDGEMENTS Fluid Fertilizer Foundation AgVise Laboratories A & L Laboratories Olsen Laboratories Western Laboratories

The Concept of Post-Emergent N Applications Why the interest?

Reduce volume of fertilizer material required at seeding. Potentially a better risk management tool for nitrogen fertilizer application in dryland cropping systems. Ability to apply N closer to the time of maximum crop uptake. Ability to fine-tune N rates more precisely based on growing conditions Why the interest?

Nitrogen Fertilizer Management Form (Right Form) Placement (Right Place) Timing (Right Time) Rate (Right Rate) Most challenging aspect

Challenge with Post-Emergent- N (PE-N) Management on the Canadian Prairies It is very difficult to improve on the no-till one-pass seeding and fertilizing system because of its proven and recognized high efficiency.

Where are we at with this concept-Part 1 ( )?

Test Crop: Spring wheat and canola PE-N application: 1, 10, 20 & 30 days after planting (UAN-surface dribble & coulter application) vs all at planting. Coulter injection reduces but does eliminate the risks associated with PE-N Biggest risk is delay in receiving significant rainfall after application. Need to consider some N at time of seeding as a way to control risks

Where are we at with this concept-Part 2 ( )? Test Crops: Spring wheat and Canola Adding some N at seeding significantly reduces the risks of post- emergent N applications. Recommend a minimum of 66% of total fertilizer N requirements as starter N Spring wheat: PE-N up to 5-6 leaf stage Canola: PE-N up to appearance of first flowers

Most Recent Studies

Where are we at with this concept-Part 3 ( )? Test Crops: Spring wheat, Canola, Durum, Oat, Malting Barley, Winter wheat Years

Where are we at with this concept-Part 3 ( )? List of Treatments Check – No N Farmer Practice (FP) (100% of recommended) at seeding NR - N Rich Strip 1.5x rate of N used in FP at seeding RR - Reduced N rate – 66% of FP at seeding 50% of FP at seeding and 50% Post-emergent 66% of FP at seeding and 34% Post Emergent 50% of FP at seeding and balance with GreenSeeker sensor 66% of FP at seeding and balance with GreenSeeker sensor

Summary of Results

Question #1: NR vs FP ResultsGrain Yield NR=FP NR>FP

Question #1: NR vs FP ResultsGrain Yield NR=FP78% NR>FP22%

Question #2: FP vs RR ResultsGrain Yield FP=RR FP>RR

Question #2: FP vs RR ResultsGrain Yield FP=RR65% FP>RR35%

Question #3: FP vs Split 50/50 ResultsGrain Yield FP=SP50% FP>SP50%

Question #3: FP vs Split 50/50 ResultsGrain Yield FP=SP50%82% FP>SP50%18%

Question #4: FP vs Split 66/34 ResultsGrain Yield FP=SP66% FP>SP66%

Question #4: FP vs Split 66/34 ResultsGrain Yield FP=SP66%100% FP>SP66%0%

The next step for split N applications…

At seedingPE-N (Split-Uniform Rate) 50% 66%34% At seedingPE-N (GreenSeeker tm ) 50%?? 66%??

Question #5: FP vs GS 50% ResultsGrain Yield FP=GS 50% FP>GS 50%

Question #5: FP vs GS 50% ResultsGrain Yield FP=GS 50%47 FP>GS 50%53

Question #6: FP vs GS 66% ResultsGrain Yield FP=GS 66% FP>GS 66%

Question #6: FP vs GS 66% ResultsGrain Yield FP=GS 66%71 FP>GS 66%29

Question #6: N Use with GreenSeeker ResultsN Use Kg/ha FP87 GS 50%48 GS 66%63

Summary ResultsGrain Yield % of trials FP=NR78%

Summary ResultsGrain Yield % of trials FP=NR78% FP=RR65%

Summary ResultsGrain Yield % of trials FP=NR78% FP=RR65% FP=50%+50%82%

Summary ResultsGrain Yield % of trials FP=NR78% FP=RR65% FP=50%+50%82% FP=66%+34%100%

Summary ResultsGrain Yield % of trials FP=NR78% FP=RR65% FP=50%+50%82% FP=66%+34%100% FP=50% + GS47%

Summary ResultsGrain Yield % of trials FP=NR78% FP=RR65% FP=50%+50%82% FP=66%+34%100% FP=50% + GS47% FP=66%+GS71%

Summary ResultsGrain Yield FP=NR78% FP=RR 65% FP=50%+50%82% FP=66%+34%100% FP=50% + GS47% FP=66%+GS 71%

What can we conclude? Successful Use of Post-Emergent N applications requires some starter N. Minimum 66% at seeding The GreenSeeker was not successful in capturing the full yield potential relative to the FP treatment in the small plot trials What about the field trials?

GreenSeeker at a Field Scale

On-Farm Trials – Treatments N applied (% recommended) TreatmentSeeding Post- emergent Farmer Practice Farmer Practice100%0% Split App. / Fixed Rate Split App. / Fixed Rate66%34% VRA w/ GreenSeeker 66%VRA N-Rich150%0%

Summary - Spring Wheat 5 field trials in total5 field trials in total N applied w/GS 15% < than FP (6-24%)N applied w/GS 15% < than FP (6-24%) Grain Yield: FP=GS 5 of 5 yearsGrain Yield: FP=GS 5 of 5 years

Treatment Locations / Years BA2005VS2005BA2006RE2006RP2006 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice VRA/GreenSeeker Spring Wheat

Treatment Locations / Years BA2005VS2005BA2006RE2006RP2006 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice 49a41a58a54a38a VRA/GreenSeeker 47a41a56a52a40a Spring Wheat

Summary – Canola 9 field trials in total9 field trials in total N applied w/GS 6% < than FP (+14 to -18%)N applied w/GS 6% < than FP (+14 to -18%) Grain Yield: FP=GS 7 of 9 yearsGrain Yield: FP=GS 7 of 9 years Grain Yield: FP<GS 2 of 9 yearsGrain Yield: FP<GS 2 of 9 years

Treatment Locations / Years BA05NH05VS05BA06KS06 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice VRA/GreenSeeker Canola

Treatment Locations / Years BA05NH05VS05BA06KS06 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice 38b56a30b36a35a VRA/GreenSeeker 42a54a33a33a34a Canola

Treatment Locations / Years RE06RP06VJ06KS07 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice VRA/GreenSeeker Canola

Treatment Locations / Years RE06RP06VJ06KS07 Total N Applied (lb/ac) Farmer Practice VRA/GreenSeeker Grain Yield (bus/ac) Farmer Practice 50a37a41a34a VRA/GreenSeeker 50a37a42a36a Canola

What can we conclude from the On- Farm field trials? GreenSeeker was able to provide equivalent grain yields to FP and in some cases better.GreenSeeker was able to provide equivalent grain yields to FP and in some cases better. GreenSeeker resulted in a more optimum rate of N fertilizerGreenSeeker resulted in a more optimum rate of N fertilizer

Where do we go from here?

Agriculture and Agri-Food Canada Agriculture et Agroalimentaire Canada Thank-you