Reconciling your Phosphate Bank Account. Norm Flore P Ag, CCA Manager Agronomic Services Agronomy Update: Jan 19, 2016 Red Deer, AB

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1 Reconciling your Phosphate Bank Account Norm Flore P Ag, CCA Manager Agronomic Services Agronomy Update: Jan 19, 2016 Red Deer, AB

2 BRIEF HISTORY OF PHOSPHATE USE IN W. CANADA

3

4 October, 1965

5 What s Happening Here?

6 Today s P Response... well managed land

7 Fertilizer P Response by Location P Response (bu/ac) 52 Site Years of Wheat % of the sites had < 3 bu/ac P response

8 Influence of Seedrow P on Yield & Maturity Yield Days to Maturity Grain Yield (bu/ac) Days to Maturity Seedrow P 2 O 5 (lb/ac) 105 Source: Westco, average of 7 Alberta based Malting Barley trials, 1987

9 Phosphate Promotes Maturity 13 lb P 2 O 5 27 lb P 2 O 5 No P

10 Change in Fertilizer P Response - Sask % Yield Increase Before 1970 After 1970

11 Point #1: Today, crops are less responsive to P fertilizer than they were 30+ years ago. Or are they??

12 A New Look at P Responses P (bu/ac) Annual P At Onset of Production Annual P Current Annual P Residual P Current with Consideration for Residual P

13 Value of Residual P Wheat Grain Yields (bu/ac) Seed Placed P Applied Yearly (lb P 2 O 5 /ac) Amount of P b cast initially (lb P 2 O 5 /ac) Figure 3. Crops respond to P fertilizer and P fertility, so depleted soil P can decrease crop yield potential (Wager, B.I., J.W.B. Stewart, and J.L. Henry Comparison of single large broadcast and small annual seed-placed phosphorus treatments on yield and phosphorus and zinc contents of wheat on Chernozemic soils. Can J. Soil Sci. 66:

14 Residual + Seedrow P = Top Yields P (bu/ac) Residual P Only 25.9 Annual Seedrow P Only Seedrow P + Residual P Source: Westco, Ellerslie, 1982 to 1996

15 Protecting the Residual Pool Annual P Residual P

16 Point #2: Residual P is critical in high yielding environments. Where did it come from? Status of my residual pool?

17 1,800 1,600 1,400 1,200 1,000 Fertilizer Consumption in W. Canada ( ) tonnes ('000) of N and P 2 O 5 Early 80 s 25 lb P 2 O 5 applied 17 lb removed in 30 bu wheat 8 lb GAIN Nitrogen Phosphate

18 + P No P

19 9 40

20 1,800 1,600 1,400 1,200 1, Fertilizer Consumption in W. Canada ( ) tonnes ('000) of N and P 2 O 5 Early 80 s 25 lb P 2 O 5 applied 17 lb removed in 30 bu wheat 8 lb GAIN Nitrogen What has changed since then? Higher yields ( 50% ) Huge acre shift to higher P consuming crops (canola) 15 million less acres of fallow Phosphate

21 P Removal vs Replenishment - Alberta 40 1, P 2 O 5 Removal (lb/ac) 1,400 lb/ac P 2 O Average Deficit of 7 lb/ac P 2 O 5 Applied (lb/ac) 1,200 1, Source: Dean Andersen, Yara 200

22 Soil Test P Levels (lb/ac P in 0-6 )* V. Low - Low Medium High to V. High % prob response 8 12 bu annual response 50% prob response 2-5 bu annual response 25% prob response 0-2 bu annual response Annual P Annual P Annual P Residual P Residual P Residual P * Modified Kelowna Methodology

23 Point #3: A bag an acre of is no longer enough for today s yield expectations. What are the implications of a sufficiency approach or applying less than removed??

24 Impact of Sufficiency Approach 15 lb P 2 O 5 /ac P (bu/ac) Annual P Residual P Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 0

25 Impact of Sufficiency Approach 15 lb P 2 O 5 /ac P (bu/ac) Annual P Residual P Rate of decline is dependent on difference between input and output. Annual P Residual P 0

26 2.7

27 Impact of Removal Philosophy P Fertilizer (credit) = Crop Removal (debit) P (bu/ac) Annual P Residual P Annual P Residual P 0 Today Future

28 Phosphate Balance for Sustainability

29 Phosphate Removal by Crop CROP P 2 O 5 Removal (lb/bu) Average Yield (bu/ac)* P 2 O 5 Removal (lb/ac) Canola Wheat Barley (78%) 47.4 (100%) 64.8 (137%) Canola: +10 lb/ac P 2 O 5 removal (30% ) Peas (83%) 26.6 Oats (160%) 19.8 * Average Alberta Yields ( )

30 Dilemma... More fertilizer P is required to maintain optimum P nutrition. Most P is Seedplaced: May not be safe to apply more. Soil Residual Levels Provide Some Latitude... Not all P needs to be seedplaced. But, target for minimum of 15 lb Not critical that removal and replacement match annually

31 Replacement Strategy with Seedrow P Seq Crop Target Yield (bu/ac) P 2 O 5 lb/bu P 2 O 5 Removal (lb/ac) Replace Opt 1 (annual) Replace Opt 2 (average) Replace Opt 3 (crop) Year 1 Wheat Year 2 Canola Year 3 Barley Year 4 Peas Year Total 148 lb (37 lb/yr) 148 lb 148 lb 148 lb

32 Safely Accommodating Higher P Rates Seedrow P Min - 15 lb P 2 O 5 /ac Max - safe rate Band Apply: Balance of required P Band Applied Fertilizer Sideband Midrow Fall applied Spring pre-plant

33 Another Approach to Ponder.... Annual P Seedrow P Min - 15 lb P 2 O 5 /ac Max - safe rate Residual P

34 4R Nutrient Stewardship Any Beneficiated Phos Excludes rock phos and organic phos Crop Removal Supplement with Soil Test History Experience Phos Minimum 15 lb at seeding Flexibility in Time and Place for Balance Band (fall or spring) sideband midrow Broadcast (fall or spring)

35 Norm Flore Manager, Agronomic Services Crop Production Services (403) cell