Marla Riekman, MAFRD Adam Hayes, OMAFRA David Lobb, U of M Mario Tenuta, U of M

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1 Marla Riekman, MAFRD Adam Hayes, OMAFRA David Lobb, U of M Mario Tenuta, U of M

2 a) Earthworms, microbes b) Good soil structure c) High yielding d) Black soil high in Organic Matter e) Earthy smell

3 Defined as "the continued capacity of soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain biological productivity, promote the quality of air and water environments, and maintain plant, animal, and human health" (Pankhurst et al., 1997).

4 What are the key parameters? What are the best options to measure these parameters? How can we make recommendations for practices to improve soil health? What is the expected impact of these management changes?

5 Soil Health Real or Abstract? Adam Hayes Soil Management Specialist OMAFRA

6 SOIL HEALTH PHYSICAL Soil compaction Water infiltration Aggregate stability ORGANIC MATTER CHEMICAL ph Potassium Phosphorus Ca, Zn, Mg, Mn BIOLOGICAL Potentially mineralizable nitrogen % Organic Matter Respiration

7 Soil Health Parameters & Measurement Parameter Lab Quick and Dirty Physical Structure Visual observation Compaction Bulk density Dig a hole (dense layer, obstructed root growth) Tile probe/ penetrometer/ flag (poor man s penetrometer) Aggregate stability Water Infiltration Aggregate stability Infiltration ring (known volume) Slaking test Surface soil crusting Visual observation (ponding) Coffee can (pour & see)

8 Soil Health Parameters & Measurement Parameter Lab Quick and Dirty Biological Soil organic matter Soil organic matter test/ organic carbon Soil life Potentially mineralizable nitrogen Solvita, other biological tests Nematodes Soil colour Zero nitrogen yield Earthworm numbers Smell Underwear

9 Soil Health Parameters & Measurement Parameter Lab Quick and Dirty Chemical Nutrients and ph Soil nutrient test Tissue tests Observed nutrient deficiencies Crop growth/ colour

10 Soil Health Assessments/ Tests Cornell Ontario samples from long term tillage and rotation trials showed significant difference in soil health score between tilled and not tilled (difference in scores was small) Several nutrient indicators can mask differences Ratings done by texture - analysis did group samples by location which were different textures The most significant indicators were organic matter level, aggregate stability and potentially mineralizable nitrogen Ontario ratings were developed for the 3 indicators Solvita, Haney (not calibrated to our fertility tests)

11 Soil Health Challenge Structure, aggregate stability, water infiltration Improving Soil Health Recommendation Crop rotation/ cover crops Organic matter additions Reduced tillage/ residue management Erosion control Soil Compaction Radial tires Low tire pressure Try to keep axel loads below 5 t/axle Reduce field traffic/ controlled traffic Drainage Improve aggregate stability

12 Improving Soil Health Soil Health Challenge Recommendation Soil organic matter Add organic amendments Crop rotation/ cover crops Reduced tillage/ residue management Soil life Crop rotation/ cover crops Organic matter additions Reduced tillage/ residue management Nutrients and ph Add nutrients (fertilizer, organic amendments) Add lime

13 Impact of Management Changes: Short Term or Long Term? Practice Short Term Long Term Crop Rotation/ Cover Crops Add Organic Amendments Reduced Tillage/ Residue Management Prevent/ Remediate Soil Compaction Erosion Control X X Depends X X X X X

14 Soil Health Synergies

15 Mario Tenuta Soil Health Panel

16 Soil Quality vs. Health? Soil Quality Soil Conditions to Predict Productivity Capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality, and promote plant and animal health (Doran & Parkin, 1994) Soil Health The continued capacity of soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain biological productivity, promote the quality of air and water environments, and maintain plant, animal and human health (Doran & Safley, 1997) Soil Conditions to Predict How Soil Functions Good Functioning Does Not Imply Good Productivity

17 What Needs to Be Examined? For Soil Health Comparison of plant yield and diversity of agricultural and natural systems Emphasis on ecological goods and services of the systems For Soil Quality Evaluation of the yield of the system based on levels of inputs Emphasis is not on ecological goods and services

18 Let s Call it Soil Health Measures/Observe Intensity measures Yield / lb fertilizer Yield / $ inputs Soil organic matter Soilborne disease levels Water infiltration rate Weed bank Post-harvest and at planting soil N

19 Ex. Soil Organic Matter Improves Corn Yield

20 Ex. Soil Organic Matter Decreases Some Diseases Tenuta et al. unpublished

21 How to Build Soil Health Rotate wisely Feed soil crop residues Minimize tillage Maintain good soil fertility, not excessive Invest in your soil (ex. drainage) Extend growth to shoulder seasons or grow perennials Use cultural practices as much as possible to lessen reliance on pesticides Have good yields Use soil tests and in-field strip trials to optimize fertility

22 Scoring Not a fan of comparing scores of different fields Am a fan of tracking the score of an individual field to get it to improve

23 Soil Health Soil Health David Lobb Department of Soil Science Watershed Systems Research Program University of Manitoba

24 Soil Health

25 The greatest threat to Soil Health is soil erosion

26 Key Soil Health parameters: 1) Adoption of conservation tillage 2) Crop residue cover 3) Soil organic matter content

27 * If farmers adopt conservation tillage, the health of the soil may not be protected Key Soil Health parameters: 1) Adoption of conservation tillage 2) Crop residue cover 3) Soil organic matter content

28 * If farmers adopt conservation tillage, the health of the soil may not be protected There are tillage operations that are more erosive than the mouldboard plough

29 * If farmers adopt conservation tillage, the health of the soil may not be protected Even seeding operations cause tillage erosion

30 * If farmers adopt conservation tillage, the health of the soil may not be protected Tertiary tillage operations can cause the most severe tillage erosion

31 * If farmers adopt conservation tillage, the health of the soil may not be protected A mouldboard plough can be used as a soil conservation tool

32 * If farmers adopt conservation tillage, the health of the soil may not be protected Key Soil Health parameters: 4) Soil movement by all forms of tillage 5) Extent and severity of soil redistribution (loss and accumulation SOM, MB) 6) Variability in biological activity (crop growth/yield)

33 ** There may be a practice that is more effective than conservation tillage in restoring soil health Soil-Landscape Restoration Returning eroded soil to the top of the slope in France in the 1930s

34 Soil-Landscape Restoration: Findings: The addition of as little as 10 cm of topsoil to severely eroded hill tops increased yields by 10% to 33% in wet years and 39% to 133% in dry years. Although, there was a significant reduction in removal plots at one of the three sites there was still a NET increase in crop production. Landscape restoration provides continued yield response on hilltops for several years after the initial restoration. The addition of topsoil improves water retention, soil nutrient status, and organic matter concentrations. Cost recovered in 4 to 6 years.

35 a) Earthworms, microbes b) Good soil structure c) High yielding d) Black soil high in Organic Matter e) Earthy smell

36 a) Residue removal/burning b) Corn-soybean rotation c) Tillage d) Pesticide use e) Excess moisture/salinity