Frenzy. Late Nitrogen. Late Nitrogen Frenzy. Ben Rosser, OMAFRA Dave Hooker, UG-Ridgetown

Transcription

1 Late Nitrogen Late Nitrogen Frenzy Frenzy Ben Rosser, OMAFRA Dave Hooker, UG-Ridgetown Adapted from: Greg Stewart (Maizex) and Jason Van Mannen (Veritas) #SWAC16

2 The 4-Rs of nutrient mgmt.

3 N rate determination? Ontario Corn Nitrogen Calculator PSNT Accuracy?

4 N rate depends on year! Guelph loam Near Elora Source: Deen et al Better Soils and Crops

5 N rate depends on year! Guelph loam Near Elora 2012: 120 lbs Source: Deen et al Better Soils and Crops

6 N rate depends on year! Guelph loam Near Elora 2012: 120 lbs 2013: 220 lbs Source: Deen et al Better Soils and Crops

7 N rate depends on year! Guelph loam Near Elora 2012: 120 lbs 2013: 220 lbs Source: Deen et al Better Soils and Crops

8 Bender et al. (2013) Agron. J. 105:

9 Sidedress 10% Bender et al. (2013) Agron. J. 105:

10 Tassel Rapid Uptake Sidedress 70% 10% Bender et al. (2013) Agron. J. 105:

11 Tassel 70% Sidedress 10% Bender et al. (2013) Agron. J. 105:

12 Tassel 70% Sidedress N Remobilization To Grain 10% Bender et al. (2013) Agron. J. 105:

13 Bender et al. (2013) Agron. J. 105: Credit: Pioneer Crop Insight March 2014

14 N Loss in Corn Fields 1) Denitrification 2) Leaching

15 Denitrification NO 3 -> NO 2 -> NO -> N 2 O -> N 2 Plant Available Gaseous Loss > Credit: Iowa State

16 Denitrification NO 3 -> NO 2 -> NO -> N 2 O -> N 2 Plant Available Gaseous Loss > Soil Temperature (C degrees) Potential nitrate loss in saturated soil (% per day) < % % > % Source: Hoeft (2002; Univ. IL)

17 Leaching NO 3 - NO 3 - NO 3 - NO 3 - NO 3 - NO 3 - Adapted from University of Nebraska - Lincoln

18 Sidedress N Credits Sidedress N Recs From Ontario N database Soil Type % of Preplant Rec <50% Sand (clay, loam, silt): 80% 50-80% Sand (sandy loam): 90% >80% Sand (sand, loamy sand): 100%

19 Soil Temperature (C degrees) Potential nitrate loss in saturated soil (% per day) < % % > %

20 Soil Temperature (C degrees) Potential nitrate loss in saturated soil (% per day) < % % > % > 75% of N Available for Loss 7-8 Weeks?

21 Equipment options

22 High Yield Contest Winners Several (Francis Childs, David Hula, Randy Dowdy) have spoken across Ontario All have promoted the concept of feeding the crop late (VT) to maximize yields.

23 Key Question. Does a late season N applic. (V10 VT) provide an economic advantage over earlier application strategies? If total N applied should be close to MERN in a typical year If total N applied is similar (+/-) across all comparisons

24 Yield (bu/ac) Ontario Nitrogen Timing Preplant vs. V and Same amount of total N, lb at different times Preplant V Norfolk Lambton Huron Bornholm Elora Huron

25 Yield (bu/ac) Ontario Nitrogen Timing Preplant vs. V6 vs. V and Same amount of total N, lb at different times Preplant V6 V10-V Norfolk Lambton Huron Bornholm Elora Huron

26 Yield (bu/ac) Ottawa Valley N Timing Locations in Grower s standard rate as SD (V6) or split (70% V6 and 30% V10-V12) V6 Split (V6 & V10-12) Location

27 Yield (bu/ac) Bruce Soil and Crop All Preplant N vs. Split N - Average of 4 locations in % Pre 70% Pre 30% V % Pre 70% Pre 30% V % Pre 50% V lb N/ac 180 lb N/ac

28 Maizex Agronomy Data, 2015 Site Base N Late N Yield Campbellford Plus 50 - June Plus 50 - July Granton Plus 50 - July Erin Plus 50 - June Plus 50 - July Millbank Plus 50 - July Langton Plus 50 - June Plus 50 - July Kingston Plus 50 - July Plus July Source: G. Stewart, Maizex Seeds

29 Becks Hybrids Data High Clearance Sidedressing

30 Beck s Hybrids 4-year average comparing traditional sidedress to V10 high clearance sidedress. 3 bu/acre response to V10 app

31 Yield loss? 31

32 Summary of little independent data (at equivalent total N) Late N application does NOT consistently increase yields (or profitability) Any late N advantage seems to disappear after VT

33 Recap: Late N Advantages Timely for crop uptake during grainfill Planting timeliness Reduce the size of the N pool and reduce the risk for loss* Rate adjustment given conditions*

34 Reducing the Nitrate Pool Leaching Lighter soil Early N moving down with moisture Denitrification Heavy soil Gaseous losses of N in saturated conditions

35 Soil N Testing (Late) What do Soil N Tests Mean once Crop N Uptake is Significant? i.e. V10 + Perhaps Nothing!

36 NO3-N (ppm) Nitrate Monitoring in Oxford County Site, Apr 9-May 23-May 6-Jun 20-Jun 4-Jul 18-Jul 1-Aug 15-Aug 29-Aug 12-Sep 26-Sep 10-Oct 24-Oct 7-Nov Year 2009 ESN138 Urea138 Control5

37 N Rate Adjustment Millbank, ON example 2015 Factor Situation Is yield potential high? High with 37,000 PPA.

38 N Rate Adjustment Millbank, ON example 2015 Factor Situation Is yield potential high? High with 37,000 PPA. May / June rain excessive? High - 9 in June

39 N Rate Adjustment Millbank, ON example 2015 Factor Situation Is yield potential high? High with 37,000 PPA. May / June rain excessive? Soil nitrate values? High - 9 in June Relatively low but what do they mean at late stages?

40 N Rate Adjustment Millbank, ON example 2015 Factor Situation Is yield potential high? High with 37,000 PPA. May / June rain excessive? Soil nitrate values? Plant colour / NDVI? High - 9 in June Relatively low but what do they mean at late stages? Fading between tiles

41 What to do after 9 inches of rain in June? G. Stewart, Maizex Seeds

42

43 What to do after 9 inches of rain in June? G. Stewart, Maizex Seeds

44 Other late N considerations Placement? Agrotain? Precision ag approaches? Hybrid effects?

45 Consider Placement.

46 Consider Agrotain Cost and loss considerations N Rate (lbs N/ac) Product Urea $38 $47 Urea + Agrotain $42 $52 UAN $44 $53 UAN + Agrotain $48 $58 ESN $51 $64 J. Van Maanen, Veritas

47 Consider Agrotain Cost and loss considerations N Rate (lbs N/ac) Product Urea $38 $47 Urea + Agrotain $42 $52 UAN $44 $53 UAN + Agrotain $48 $58 ESN $51 $64 J. Van Maanen, Veritas

48 Agrotain? Yes to some of these Qs? Is the soil damp at the surface? Is there significant residue on the soil surface? Is the weather forecast dry? Is the canopy fully developed?

49 Consider precision ag approaches Do sensors (i.e. GreenSeeker) give you more meaningful information later in the season? -- YES! What does it mean though

50 Source: Veritas Consider precision ag approaches Greater variation in NDVI at V12 compared to V3 Much greater plant uptake at V12 V3 V12

51 Future: hybrid-specific responses NDVI Visual Source: Dr. Tony Vyn, 2015

52 Late N Conclusions!! 1. Does NOT consistently increase yields or $ 2. Economic benefits possible with in-season mgmt. 3. Possible environmental risk lowered with multiple apps 4. Agrotain: Urea likely benefit more than 28%

53 Conclusions 5. Soil N tests later than PSNT likely not useful 6. N uptake likely needed by VT 7. Sensor opportunities 8. Hybrid-specific N responses may be an opportunity 9. Much more Ontario research is required

54 QUESTIONS? Ben Rosser Dave