2019 SWCS International Annual Conference July 28-31, 2019 Pittsburgh, Pennsylvania

1. White Clover as a Living Mulch in Georgia: Transferring
a Crop Production System to Improve Soil Health
Nick Hill, Zack Sanders, Josh Andrews, Jill Mullican, Miguel Cabrera,
Uttam Saha, David Radcliffe, Matt Levi, and Bill Vencill
Crop/Soil Sciences; Feed and Environmental Water Lab
Univ. of Georgia

2. Publications for Specifics
Sanders Z.P., J.S. Andrews, U.K. Saha, W. Vencill, R.D. Lee, and N.S. Hill. 2017.
Optimizing agronomic practices for clover persistence and corn yield in a white
clover – corn living mulch system. Agron. J. 109:2025-2032.
Sanders, Z.P., J.S. Andrews, and N.S. Hill. 2018. Water use efficiency in living mulch
and annual cover crop corn production systems. Agron. J. 110:309-317.
Andrews, J.S., Z.P. Sanders, M. Cabrera, U.K. Saha, and N.S. Hill. 2018. Nitrogen
dynamics in living mulch and annual cover crop corn production systems. Agron. J.
110:1309-1317.
Andrews, J.S., Z.P. Sanders, N.S. Hill, and D.E. Radcliffe. 2019. Simulated nitrate
leaching in annually cover cropped and perennial living mulch corn production
systems. Accepted – J. Soil Water Conservation.

3. Funding - $1.95 Million

4. Zack Sanders Josh Andrews Jill Mullican
The Graduate Students

5. The Living Mulch Concept

6. 10 Research/Economic Questions
1. What planting configuration?
2. What ecosystem services?
3. How to manage crop residue?
4. Effect on soil health?
5. How much yield?
6. Economic robustness of LM system?
7. How does the LM system affect water use?*
8. What are the N dynamics of the LM system?*
9. How does the system affect nitrate leaching?*
10. What other row crops can we use?*

7. Q 1. What is the best planting configuration for the system?
36 inch row, 8-10 inch band
28 days after harvest
36 inch row, 8-10 inch band
56 days after harvest
30 inch row, 16 inch band
28 days after harvest
30 inch row, 16 inch band
56 days after harvest

8. Q 2. What ecosystem services are provided by living mulch?
• Provides N to the Crop (30# vs 250# /A)
• Prevents Erosion and Runoff
• Reduced N leaching
• Builds Soil Health
• Minimizes Pesticide Inputs
• Pollen Source for Honey Bees
Cereal Rye
5” rain in 3 hrs
Before LM 2 yrs LM
Developing O Horizon
Living Mulch

9. No-till corn system Living mulch system
Oct. 1
Jan. 6
Cereal Rye Living Mulch
Q 3. How do we manage corn residue to permit clover regrowth?

10. Treatment Added N Bulk Density Porosity Ksat
* Water hold Labile C
kg ha-1 g cm-3 % cm hr-1 cm3 cm-3 mg kg-1
No cover 250 1.41 47.0 1.83 46.7 549
Cereal Rye 250 1.40 47.0 2.98 46.3 579
Crim. Clover 150 1.36 48.7 3.21 46.3 640
Living mulch 30 1.25 52.3 4.72 47.0 780
Q 4. What is the impact of living mulch on soil health?
*Guelph permeameter (tension infiltrometer)

11. Treatment Added N
Yield
(4 yr avg)
~lb/A Bu/A
Living mulch 30 176
Crimson clover 150 203
Cereal rye 250 202
Q 5. What is the impact of living mulch on corn yield?

12. Q 6. What is economic return
above variable costs?
(4 yr yield avg)
Current N price ~ $0.62/lb
Corn @ $4.29
Corn @ $4.29

13. Research Summary
• Production parameters:
Wider rows, narrow clover band
• Ecosystem services:
Provides N to crop, Less runoff and erosion, Reduced N leaching,
Fewer herbicides, Pollen for bees over extended period
• Soil health:
Lower BD; Increased macropores, Saturated water flow, Labile C;
No change in water holding capacity
• Corn yield/economics:
Lower yield (-12%)
Lower costs make LM system more economically robust

14. Where Do We Go From Here?
• Outreach/Demonstration
Field Days On-Farm Demonstrations

15. Farm Demonstration Sites
Corn – Lee and Irwin Counties
Cotton – Burke County, GA
Elmore County, AL

16. Farm Demonstration Sites
Corn – Lee and Irwin Counties
Cotton – Burke County, GA
Elmore County, AL

17. Corn
Lee County, GA

18. Corn
Irwing County, GA

19. June 26, 2019
July 3, 2019
Cotton
Burke County, GA

20. Cotton
Elmore County, AL
July 1, 2019

21. Summary Outreach
• A Learning curve at the farm
Prior experience helps
• Even with failures at first try:
Farmers see value and willing to adjust
• Topics for TRAINING VIDEOS – (Pennington Seed Company)
- Philosophy and benefits - Mineral nutrition considerations
- Clover establishment - Harvesting row crops
- Banding herbicides - Post harvest residue management
- Planting row crops - Alternate year considerations

22. Where Do We Go From Here?
Partial Retirement
Go Dawgs!!