SOIL HEALTH FROM AN ORGANIC FARMER S PERSPECTIVE. Presentation to the Summit on Canadian Soil Health 2017 By Ken Laing BSc[Ag] St.

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1 SOIL HEALTH FROM AN ORGANIC FARMER S PERSPECTIVE Presentation to the Summit on Canadian Soil Health 2017 By Ken Laing BSc[Ag] St.Thomas, ON

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7 THE PREDICAMENT Declining soil health is related to soil carbon losses [SOC =.58 SOM] Climate change is related to increasing carbon [as CO2]in the atmosphere

8 SOIL DEGRADATION the world s cultivated soils have lost between 50 and 70% of their original carbon stock, much of which has been oxidized upon exposure to the air to become CO2 Rattan Lal - director of Ohio State University s Carbon Management and Sequestration Center

9 HANEY SOIL TESTS at Orchard Hill Farm 2015 VEGETABLE FIELD ORGANIC MATTER 3.1% SOLVITA CO2 BURST 39.8 SOIL HEALTH # 7.85 FENCE ROW ORGANIC MATTER 6.4% SOLVITA CO2 BURST SOIL HEALTH # 19.4

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11 THE CARBON CYCLE Plants take CO2 carbon as a gas- from the air and through photosynthesis create sugars - carbon as a liquid- part of these sugars support plant growth and development but a very significant portion 30% is exuded through the roots to feed microbes in return for nutrients and disease protection

12 THE TERRESTRIAL CARBON CYCLE IT IS A LIVING SYSTEM DRIVEN BY SOLAR ENERGY Farmers manage a good size chunk of this terrestrial biosphere

13 THE SOIL IS A HUGE CARBON STORE IN THE TERRESTRIAL BIOSPHERE

14 3500 Carbon Content of Terrestrial Biosphere Components - Gtonnes Soil Depth (.3, 1, 2m) Atmosphere Vegetation Eswaran et al[2000] Jobbagy and Jackson[2000] Jungkunat et al[2012] Bates[1996] Xu[2011]

15 IPCC report on the Carbon Budget of Terrestrial Ecosystems adapted from Steffen et al., 1998

16 COMPARISON OF WOODS SOIL TO ADJACENT FIELDS at Orchard Hill Farm WOODS SOIL OM 4.8% [2012] No disturbance ADJACENT FIELDS OM 2.19 %[ 81] Rhubarb OM 4.2% [2012] Planting about 15 years old Very little disturbance Mulched heavily with hay at least every 2 years Fruit orchard OM 5.3% [2007] Planting about 30 years old Permanent grass ground cover

17 ORGANIC MATTER INCREASES AT ORCHARD HILL FARM Baseline OM s fields range 1.37% -3.02% Average increase 55% over baseline range now 3.0% - 4.2% Range of increase 22% - 126% 126% from reclaimed gravel pit area [1.37%-3.11%]

18 THE RELATIONSHIP BETWEEN SOIL ORGANIC MATTER AND ATMOSPHEREIC CO2 There is as much carbon in 6 of soil with 1% organic matter as there is in the atmosphere above a field. If the organic matter decreases from 3% to 2%, the amount of carbon dioxide in the atmosphere could double. from Building Soils for Better Crops Fred Magdoff and Harold Van Es, 2009

19 Sara Wright USDA ARS IN 1996 SHE DISCOVERED GLOMALIN

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21 GLOMALIN -glomalin is produced by mycorrhizal fungi - The plants share 30-40% of their photosynthate with mycorrhiza and other microbes in the rhizoshere in return for nutrients, water and disease control -glomalin can make up 27% of Carbon in undisturbed soils - 27%x1600billion tonnes = 430 billion tonnes C -it has a very slow turnover rate of between 7-42 yrs.

22 THIS IS A WHOLE NEW PATHWAY TO GET CARBON INTO THE SOIL We are not just dependent on decomposition of residues for adding stable SOC It does necessitate having living plants/roots in the soil as much as possible Perennial crops really shine here Annual crops require strategies integrating continuous no-till, cover crops and livestock

23 SUMMARY OF THE NEW SOIL/PLANT MANAGEMENT PARADIGM NO BARE SOIL FILL IN BROWN GAPS WITH LIVING COVERS WHETHER BETWEEN ROWS OR AFTER HARVEST REDUCE OR ELIMINATE DISTURBANCE[TILLAGE] INTEGRATE LIVESTOCK

24 THE MAJOR CHALLENGE FOR ORGANIC FARMERS IN THIS NEW PARADIGM IS REDUCING TILLAGE WE USE TILLAGE TO TERMINATE PREVIOUS CROPS WE USE TILLAGE TO CONTROL WEEDS ORGANIC NO-TILL/STRIP TILL IS VERY MUCH IN ITS INFANCY

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38 TECHNICAL/SCIENCE GAPS How can we speed the transfer of Carbon to the soil? Is modern plant breeding with it emphasis on maximum grain yield sacrificing root exudates and carbon transfer to the soil thus reducing aggregate formation? How are fertilizer materials particularly nitrogen and phosphorous affecting soil microbes and carbon accumulation in the soil? If root exudates are so critical should we not seek out crop plants with larger root systems?

39 LACK OF SUPPORT A quick search of OMAFRA s and Ag Canada s websites for information on organic no-till or permaculture did not come up with anything useful No programs and $ to reward farmers for sequestering carbon in soils

40 THE HEALTH OF THE SOIL, PLANT, ANIMAL AND MAN IS ONE AND INDIVISIBLE LADY EVE BALFOUR