1. Jamie long, C.C.A. Josh Gunther, C.C.A.
Feed the Bean
Jamie long, C.C.A.
Josh Gunther, C.C.A.

2. Six secrets to soybean success
Weather
Fertility
Genetics/Variety
Foliar protection
Seed treatment
Row spacing
Dr. Fred Below, University of Illinois

3. Liebig’s law of the minimum
Weather
Fertility
Genetics/Variety
Foliar protection
Seed treatment
Row spacing
Dr. Fred Below, University of Illinois

4. Who already fertilizes their soybeans?
Poll question:
Who already fertilizes their soybeans?
Following corn?
Following soybean?

5. Historical fertilizer practices
Fertilize prior to corn, let soybeans scavenge the nutrients
N, P, K, lime according to soil tests and removal rates for both corn and soybean
How could this limit soybean yields?

6. 230 bu corn
60 bu soybean
How would this vary based on higher yields poll the crowd

7. Why fertilize soybeans?
To achieve higher yielding soybeans

8. So now you’re going to fertilize your soybeans….
What do you apply? When do you apply?

9. What are your current nutrient levels?
First things first…
What are your current nutrient levels?

10. Soil testing Necessary for knowing soil nutrient levels
Above optimum levels of nutrients – don’t need to fertilize

11. Tissue testing Help track in-season deficiencies
Top trifoliate – reproductive stages
After deficiency is determined, yield is already lost

12. Correct pH
For soybean: 6.0 to 6.8

13. Macronutrients
Nitrogen (N)
Potassium (K)
Phosphorous (P)

14. Nitrogen uptake by soybeans
How do soybeans meet their nitrogen requirement?
Fix N through symbiotic relationship with Bradyrhizobium japonicum
Nodules
Mineralized nitrogen from soil
From previous corn crop
Organic matter
Majority comes from N fixation
Higher o.m. more nitrogen – each percent of organic matter can provide 10 to 30 lbs of n

15. University of Delaware
How would different organic matter percentages alter this - discuss
University of Delaware

16. Make sure and explain green vs blue dot
Nafziger Bulletin 2015
In these trials the N has been applied as urea, urea with urease inhibitor (Agrotain®), and/or polymer-coated urea (ESN) that slows release. Rates have ranged from 100 to more than 300 lb of urea (45 to 150 lb of N) per acre, and applications have been made between first flower (R1) and R4, or full pod stages.

17. Is a N application needed?
Very high yield environments increase the likelihood of seeing a positive yield response
R3 timing
Early season N – can help in environmental conditions where nodulation is delayed
Before applying N – make sure it is the only limiting nutrient
Early season N – not economic

18. Potassium (K)
Arguably more important in soybean production than Phosphorus
K deficiency proven to have more of a yield restriction than P deficiency
Must maintain K levels above the Critical Level
We all know N.P &K. Switching to N K & P for soybeans

19. Michigan State University Extension
What is the Critical Level?? Where 95-97% of the crops yield potential will be reached without any additional inputs
Michigan State University Extension

20. Potassium Critical level
Multiply CEC X 2.5 and add 75 [(CECX2.5)+75]
Ex If you have a soils where the CEC is 12meq per 100g the critical level for K is 105ppm
[(12X2.5)+75]=105ppm K
Maintenance Range for K is 30ppm
Ex maintenance range is ppm

21. Michigan State University Extension

22. Buildup Range: <Critical Level
Higher recommendation than removal rate
Maintenance Range: Between Critical and Maintenance Limit
Recommend removal rate
Drawdown Range: >Maintenance Limit
Recommend lower than removal rate

23. Removal Rate of K Soybeans remove 1.4lbs of K20/bu
Ex 80bu/ac field 80x1.4= 112lbs K2O
If we need to replace 112lbs K2O that would be 187lbs Muriate of potash (0-0-60)/ac
112/.6=187

24. K recommendation will change slightly with soil’s CEC
University of Illinois & Robert Mullen Ph.D.

25. Phosphorous (P) More straight forward than K Critical Level – 15ppm
Maintenance Range – 15 – 30ppm

26. Michigan State University Extension

27. Removal Rate P Soybeans remove 0.8 lbs P2O5/bu
Ex 80bu/ac field 80 x 0.8= 64lbs P2O5
If we need to replace 64lbs P2O5 that would be 123lbs of MAP or 139lbs of DAP
64/.52=123lbs MAP
64/.46=139lbs DAP

28. P recommendation will change with different yield levels.
University of Illinois & Robert Mullen Ph.D.

29. Application Methods -Broadcast -Deep Banding -2X2 Starter -Foliar
-Broadcast performs equal to or better when above Critical Level
Best if lightly incorporated
-Band applications are most effective if below Critical Level
Poll crowd what are they finding most beneficial, what methods they use etc

30. Secondary nutrients
Calcium
Magnesium
Sulfur
Calcium and Magnesium ok

31. Sulfur for soybeans Lack of atmospheric deposition – declining sulfur
Sulfur may be limiting especially in coarse- textured soils that are low in O.M.
If lacking sulfur – apply prior to planting
Dr. Shaun Casteel, Purdue – consistent increase with S additions
Ammonium sulfate or gypsum
20 lb / A
Sulfur can reduce nodulation

32. Micronutrients Boron Chlorine Cobalt Copper Iron Manganese Molybdenum
Nickel
Zinc
This is all of them

33. What are micronutrients?
Essential plant nutrients used in very small amounts
Unlike macronutrients – removal rates are not calculated
May become limiting with higher yielding soybeans

34. What about for 100 bu soybeans?
Removal rates
What about for 100 bu soybeans?

35. Micronutrient research
No consistent yield response and sometimes negative response (Boron)
Consider soil and tissue test results
Soil and environmental conditions

36. Prediction from soil test

37. Prediction from tissue test

38. When are micronutrients recommended?
Cross off ones that aren’t in this area?

39. Foliar applications – University Research
Applied at R3
24 rows wide
Michigan State
What is blackmax 22

40. Summary
Conduct regular soil and tissue sampling to identify limiting factors
pH, K, P, possibly N and S
Consider return on investment of fertilizer applications
Conduct replicated trials on your farm

41. Six secrets to soybean success
Weather
Fertility
Genetics/Variety
Foliar protection
Seed treatment
Row spacing
End with this slide
Focusing on fertility is one way to increase yield but must use best management practices to get high yielding soybean
Dr. Fred Below, University of Illinois

42. Questions?