Management practices that build soil health-

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1 Management practices that build soil health- protecting the thin layer that stands between us and starvation Jane M.F. Johnson A.K.A Soil Lorax USDA-ARS-North Central Soil Conservation Research Lab

2 GRAND challenge Feed 9 Billion AND protect the Planet Need to roughly double food production Intensification- doing more with current ag lands Extensification converting land to food production USDA-ARS

3 Management and soil health Increasing SOC improves soil health Organic C is the backbone of SOM Stores C in soil (CO 2 out of atmosphere) Increase resilience against compaction, erosion Improve water holding capacity Promote soil productivity USDA-ARS

4 Agricultural management Crop crop rotation Tillage Residue management Fertility fertilizer Liming Crop protection Water management For most farmers profitability is the overruling factor htm Soil Health needs to promote profitability USDA-ARS-NCSCRL

5 Crops >2 crop rotation Benefits Reduce soil borne pathogens Non-host, alter soil environment, direct inhibition Improve weed control Enhance above and below ground diversity Increase soil biota (e.g. MBC) C/S<C/S/W/A Increase SOC C/S<C/C<3+ crops Especially if perennials added Lack of economic markets may limit adoption USDA-ARS

6 Management and soil health - Tillage Wade, et al USDA-ERS pdf. USDA-ARS

7 Courtesy D. Reicosky Severe winter wind erosion -naked fields -little snow cover -very cold -extreme winds Preventable. Courtesy J Pikul Courtesy D. Reicosky USDA-ARS

8 Soil aggregation Biomass Soil Years Tillage Removed Retained Citation Wind-erodible aggregates Sandy clay loam Mollic Cryoboralf Sandy Loam Typic Cryoboralf Clay Loam Mollic Cryoboralf Loam Udic Boroll Loam Mollic Cryoboralf Sandy Clay Loam Mollic Cryoboralf Clay Loam Udic Boroll Clay Loam Cryptic Hapludoll % <1 mm 4 Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled Malhi (et al., 2006) Malhi & Kutcher (2007) Singh & Mahli (2006) Mahli & Lembke (2007) Singh et al. (1994) 7 Tilled Johnson and Strock pending 2016 No Tillage Tillage increases the soil particles that are wind erodible

9 Tillage and hydrology Johnson Strock et al. in review

10 SOC and tillage 0.40 ± 0.61 Mg C ha -1 annually ( 30 cm) 44 treatment pairs Midwest reviewed by Johnson et al., 2005, Soil Till Res 83: ± 2.42 Mg C ha -1 ( 10 cm); ± 1.61 Mg C ha -1 (20-40cm) treatment pairs reviewed by Luo et al Increase or decrease in SOC related to yield response 74 studies reviewed Ogle et al. 2012

11 Tillage: No Till/Reduced Advantages Reduce erosion risk Increase surface SOM Increased bearing strength reduced damage from traffic Improved soil pore structure Improved infiltration Increase soil biological activity Improve Economic yield Disadvantage Cooler soil temp at planting Wetter near surface Higher Bulk density Nutrient stratification More at surface Reduced surface ph Agronomic yield loss possible USDA-ARS-NCSCRL

12 Residue management

13 Primary roles of crop biomass Protect the soil from erosion Build and maintain soil organic matter/soil organic carbon Soil organic matter contributes to many of the soil properties associated with highly productive soils. USDA-ARS

14 Figure 1. Ratio of soil loss with specified amount of residue cover for bare soil under high erodibility conditions) (Merrill et al., 2006). 1.2 Theoretical soil loss ratio Water erosion Wind erosion Soil cover (%) USDA-ARS

15 USDA-ARS

16 Soil aggregation Biomass Soil Years Tillage Removed Retained Citation Wind-erodible aggregates Sandy clay loam Mollic Cryoboralf Sandy Loam Typic Cryoboralf Clay Loam Mollic Cryoboralf Loam Udic Boroll Loam Mollic Cryoboralf Sandy Clay Loam Mollic Cryoboralf Clay Loam Udic Boroll Clay Loam Cryptic Hapludoll % <1 mm 4 Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled No tillage Tilled Malhi (et al., 2006) Malhi & Kutcher (2007) Singh & Mahli (2006) Mahli & Lembke (2007) Singh et al. (1994) 7 No Tillage Johnson and Strock pending 2016 Tilled Residue harvest increases wind erodible particles

17 Hydrological Response to Crop Residue Harvest Water Infiltration (cm. hr -1 ) Aquic Hapludalf (SiL) Typic Hapludult (SiL) 5 Mollic Epiaqualf (CL) Extent of Crop Residue Harvest (%) Ohio 3 locations; 2.5-yr study Corn; No tillage Data from Blanco-Canqui & Lal (2007) Geoderma 141: Morris, MN, no tillage Shift in pore space with residue removal. Johnson and Strock, in review USDA-ARS

18 Water Runoff Response to Residue Harvest Fraction of Rainfall as Runoff Minnesota - Udic Haploboroll Minnesota - Udic Haplustoll Nigeria - Oxic Paleustalf Extent of Crop Residue Harvest (%) Data from Erenstein (2002) Soil Tillage Res. 67: Data from Lindstrom (1986) Agric. Ecosyst. Environ. 16: USDA-ARS

19 Soil biological response Biomass Soil Location Removed Retained Citation Earthworms (no m -2 ) Silty clay Silty clay loam Finland Nuutinen (1992) Sandy loam Not reported N Z Fraser & Piercy (1998) Silt loam WI Karlen et al., (1994) Clay loam tilled MN Weyers unpublished 2014 Clay loam NT MN Weyers unpublished 2014 Microbial C (mg kg -1 ) Silt loam WI Karlen et al., (1994) Loamy sand Denmark Debosz et al., (1999) Sandy clay Mexico Limon-Ortega et al. (2002) Sand-Loamy Canada sand Spedding et al. (2004) Clay Loam MN Johnson and Acosta- Martinez - unpublished Clay Loam MN Johnson and Acosta- Martinez - unpublished Removing residue can reduce soil fauna

20 Stover to retain (Mg ha -1 ) Soil Organic Carbon Water Erosion Wind Erosion Moldboard plow 5.25 Continuous corn No or conserv. tillage Moldboard plow Wilhelm et al., 2007, AJ 7.90 No or conserv. tillage Corn-soybean Stover to retain (ton acre -1 ) ΔSOC (SOC n SOC i ) is proportional to annual input

21 Minimum biomass inputs depends on 2.9 ± 1 ton/acre (6.4 ± 2.19 Mg ha -1 yr -1 ) corn stover [n=35], 2.6 ± 1 ton/acre (5.74±2.36 Mg residue ha 1 yr 1 )[n=49] Precipitation and temperature Crop/rotation Nutrient management Additional inputs (e.g. manure, cover crops) US Johnson et al., 2014

22 Nutrient Nutrient removal function of Concentration Quantity of residue removed Harvest frequency For every Harvest ton/acre ear and above only 0.7% N, 0.1% P and 0.9 % K (Johnson et al. 2010) 14 lbs N, 2 lbs P and 18 lbs K per acre Karlen et al., 2014 USDA-ARS Kg/ha * = lbs/acre

23 Bioenergy-rules of thumb Photo: W. Wilhelm Yield > 175 bu per acre (~11 Mg per ha) 2.9 ton/acre (5.74±2.36 Mg residue ha 1 yr 1 ) Reduce tillage Monitor soil fertility Add other mitigating practices Cover crop Perennial on the landscape USDA-ARS

24 Wilhelm et al 2010

25 Cover crops and soil health Keeping the land covered Providing organic inputs Contribute to nutrient cycling Cover crop species matched to role

26 Diversification and Soil Health Living mulches Oilseeds Double or relay cropping Cover Crops Slide courtesy D. Karlen

27 Carbon Crop Study Cover crops used to offset harvesting stover, straw or stubble

28 Above: Winter rye in corn Above: Hairy vetch and wheat regrowth Right: Hairy vetch -soybean

29 Cover crop as C source Comparing C/S rotation residue retained to residue harvest plus cover crop No difference in particulate organic matter No difference in total C or total N Preliminary analysis suggests inclusion of cover crop offset harvesting residue

30 Cover crop and N study forage/tillage radish annual rye grass no cover crop. N-Rates 1X (170 lbs N) ½ X (85 lbs) ¼ X (42.5 lbs) 0X (no N, control)

31 Annual ryegrass Fall 63 lbs/ ac (71 kg N/ha -1 ) Kg/ha -1 Shoot Root R:S Trial Trial

32 Forage Radish 40 lbs/ ac (45 kg N/ha -1 ) Kg/ha -1 Shoot Root R:S Trial Trial Kg/ha * = lbs/acre

33 Corn Yield Mg/Ha Control Annual ryegrass Forage radish Control Annual ryegrass Forage radish X= 191 kg-n/ha Relative N applied 10 8 Corn Yield Mg/Ha Relative N applied

34 Experiment Summary: provide surface cover reduce erosion risk cover crops capture fall-available N,??reduce the need for N-inputs??attenuate Nr loss and its down-stream consequences difference between winter kill and winter surviving

35 Relay-cropping Cover crop/ca$h crop Russ Gesch Soybean planted late April early May Height W. Cam. 31 in. Relay-Soy 11 in. Mono-Soy 14 in. Camelina harvest in June

36 Slide curtesy R. Gesch

37 Dual Crop Oil Yields Winter camelina Soybean Oil yield (L ha -1 ) DC-Soy Swath-DC-Soy Relay-Soy-NR Relay-Soy-YR Mono-Soy Cropping treatment Slide curtesy R. Gesch

38 Cover crops Benefits Erosion Control Organic inputs Encourage beneficial organism Root channels N capture Challenges Timing of N availability Short planting window in Northern climates Inter-seeding trials Novel combination Water availability in semi-arid

39 Management choices can cause Degrade structure & aggregation Compaction & crusting Water & wind erosion Reduced plant growth Impaired soil biology Decreased yield Reduced Soil Productivity Slide courtesy D. Karlen

40 Improve infiltration Or management can.. Enhance structure & aggregation Avoid Water & wind erosion Diversify plant growth Increase yield Increase soil biology and function Build Resilient Health Soil

41 Aggrading choices USDA-ARS-NCSCRL

42 Management practices that build soil health- for today and tomorrow

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