11th International Drainage Symposium August 30-September 2, 2022 Des Moines, Iowa

1. Do Newly Drained Fields Need Revised
Fertility Recommendations?
Dr. Lindsay Pease, Dr. Anna Cates, Aaron Frankl, Kyle Sherbine
Dept of Soil, Water, and Climate
Northwest Research & Outreach Center
University of Minnesota Twin Cities
September 1, 2022
International Drainage Symposium
Des Moines Iowa

2. Irregular and higher intensity rain events to
occur under future climate projections…

3. Drainage is a large-scale management change
that is being used as an adaptation strategy

4. Location and Layout
• Crookston, MN (NWROC)
• Silty clay loam
• 60 acres total
• Tile installed 2019 (1 meter
deep, 15 meters apart)

5. (Transforming Drainage, 2018)
Clay-rich soils
require
drainage

6. (Minnesota DNR)

7. Crookston has the Coolest
Drainage Plots in Minnesota
• Monitoring nutrient cycling in a newly
drained field
• Baseline phase for future 4R nutrient
management treatments
• Two Growing Seasons in the books:
2020 and 2021

8. Precipitation for the 2020 and 2021
Growing Seasons (modified water year)
0
1
2
3
4
5
6
7
8
Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug
Precipitation
(inches)
2020 2021 30-Year Average

9. 2019
2020
2021

10. 2019 2020 2021
Wheat Soybeans Wheat
Drained 4220 (40) 2350 (70)a 3130 (60)b
Undrained 4200 (36) 1970 (80)b 3430 (50)a
Yield (kg/ha) was affected by drainage
Drained

11. 2021 was water limited
*
*
Lower yield variability in drained plots

12. Soil
Moisture
2020
2021
Lift Stations Turned On

13. N2O
N Losses by Pathway
N Uptake Subsurface Total
13

15. 2020: Drained < Undrained
15

16. 16
2021: Drained < Undrained

17. N2O
N Losses by Pathway
N Uptake Subsurface Total
17

18. 2019 2020 2021
Wheat Soybeans Wheat
Drained 4220 (40) 2350 (70)a 3130 (60)b
Undrained 4200 (36) 1970 (80)b 3430 (50)a
N uptake (kg/ha) estimated from yields
88.6
Drained
88.2
65.7
72.0
129.3
108.3

19. N2O
N Losses by Pathway
N Uptake Subsurface Total
19

21. N2O
N Losses by Pathway
N Uptake Subsurface Total
21

22. Differences in losses
between the two years?
22

23. N2O
2020: Drained > Undrained
N Uptake Subsurface
4 kg ha-1
5 kg ha-1
129 kg ha-1
108 kg ha-1
50 kg ha-1
0 kg ha-1
Total
183 kg ha-1
113 kg ha-1
23

24. N2O
2021: Drained = Undrained
Yield Subsurface
5 kg ha-1
6 kg ha-1
66 kg ha-1
72 kg ha-1
3 kg ha-1
0 kg ha-1
Total
78 kg ha-1
74 kg ha-1
24

25. Soil Sampling

26. Pre-plant Soil Nitrate
Kg ha-1

27. *
*
Kg ha-1 Kg ha-1
Pre-plant Soil Nitrate

28. *
* *
*
Kg ha-1
Kg ha-1 Kg ha-1
No Drainage 1 Year of Drainage 2 Years of Drainage
Pre-plant Soil Nitrate

29. Conclusions
● In undrained section, soil N2O losses are greater, but at a
smaller magnitude than yield uptake and drainage
discharge
● Yield drop in 2021 was likely due to drought, not N
deficiency
● NO3 is moving downward but we’re primarily removing
excess N from the soil profile at this point
29

30. Thank you!
• Dr. Jeff Strock
• Dr. Fabian Fernandez
• Dr. Katy Chapman
• Heidi Reitmeier
• Leah Grimm
• Peyton Loss
• Cameron Fleisher
• Ethan Erdeman
And to our sponsors:

31. Do Newly Drained Fields Need Revised
Fertility Recommendations?
Dr. Lindsay Pease, Dr. Anna Cates, Aaron Frankl, Kyle Sherbine
Dept of Soil, Water, and Climate
Northwest Research & Outreach Center
University of Minnesota Twin Cities
September 1, 2022
International Drainage Symposium
Des Moines Iowa

32. The Haney Test: Not just for soil health!
• Used to predict available N in the soil
• Potentially Mineralizable Carbon
• Water Extractable Organic
• Water Extractable Organic Nitrogen
• Can be used to predict N credits
• Ward Laboratories (Kearney, NE)
Sherbine et al (in prep)

33. CO2
CO2 + CH4
Organic
C
Inorganic
C
Stabilized C
Old C
Active
C
Potentially
Mineralizable
Carbon (PMC)
• Microbial processing
capacity

34. CO2
CO2 + CH4
Organic
C
Inorganic
C
Stabilized C
Old C
Active
C
Water-extractable
organic carbon (WEOC)
and nitrogen (WEON)
• Microbial food source
Organic
N

35. 2020/2021: No treatment differences in
PMC, WEOC or WEON

36. No difference in N credits according to
the Haney Test
• PMC and WEOC/WEON were not influenced by
subsurface drainage
• N credits could range from:
• 0.1 to 19 kg/ha in spring 2020
• 0.8 to 15 kg/ha in spring 2021