The Understanding around Soil Compaction in Crop Production John Fulton CompactionSmart, Waterloo, ON
Your decision on field operations / practices: Right decision Wrong decision
NDVI Image Early July Corn Identifying Man- / Machine-made Vs. Natural variability
Soil Preferred Composition Mineral Matter 45% Soil is Alive bacteria and other organisms Water 25% Air 25% Soil is Porous pore spaces absorb air and water plus deliver nutrients Organic Matter (OM) 5% Soil is Nutrient-Rich N, P, K and other micros vital to plant nutrition
Soil Compaction soil particles compressed together, reducing pore space. Biological Physical Chemical Image Source: www.extension.umn.edu/agriculture/tillage/soil-compaction
Soil Compaction decrease in soil volume and porosity, or increase in soil bulk density due to mechanical stress. Compaction could also be cause naturally. Surface Compaction compaction that occurs at the upper soil layer; considered within the tilled layer of soil. Subsoil or Deep compaction compaction that occurs below the tilled layer as a result of surface loading.
Decreased infiltration Reduced nutrient uptake Reduced root developed and rooting depth Reduced water holding capacity Increased soil erosion Crop YIELD!
Soil Compaction in Crop Production Mass is mass for machinery and implements (e.g. axle loads) 70% of a field can be trafficked annually Improving soil health reduces influence of machinery loadings Enables soil to recover quicker. 75% to 80% of soil compaction occurs on 1 st pass Repeated loadings increase soil compaction Heavy traffic soils retain moisture longer, recharge slowly and warm up slower. Delays in emergence Can reduce corn yield between 10-35 bu/ac and up to 60% in poor conditions. 10-ton axle loads or greater significantly increase the potential. Requiring improved farm management to deal with compaction.
Machinery Compaction Soil conditions (wet vs. dry) Excessive machine/implement loading Axle load Wheel configuration / Tracks Frequency of loading (75% to 80% of compaction occurs on 1 st pass) Soil structure
Soil Moisture moisture at the time of field operations impacts level of soil compaction. Dry compaction can promote good seed-soil contact at planting. Wet increased potential of compaction; decreasing aeration and nutrient uptake while increasing denitrification and root disease. Image Source: Wolkowski and Lowry, 2008
Soil Moisture increase in moisture increases depth of influence. Image Source: Sohne, Agricultural Engineering
Soil Texture: Bulk Density vs. Soil Resistance Bulk Densities that limit root and crop growth Hand Penetrometer (2 Mpa) Constant insertion velocity = 1.2 in/sec (28 mm/sec)
Augment or Mitigate Soil Compaction Avoidance Machinery and implement decisions Axle loads Right tool for the right job Timing of field operations Tillage Build Soil Health
Soil Resistance Food, Agricultural and Biological Engineering
Loading Interaction with Soil Point loading Area loading o Implement type and configuration o Tire configuration o Tire pressure o Tracks
Vertical Tillage (VT) Residue fractionation - break down tough corn residue more quickly for improved seedbed next spring. Sold as a low impact form of tillage Not a form of input incorporation Point loading Consider soil conditions when operating!
Tandem Disk Harrow Food, Agricultural and Biological Engineering
Soil Resistance by Implement Source: www.extension.umn.edu/agriculture/tillage/soil-compaction
Biology of Soil Compaction 5 ways Soil Organic Matter Resists Soil Compaction Surface residue resists compaction; sponge to absorb weight and water. Organic residues are less dense than soil particles. Roots create voids and spaces for air and water. Roots act like a biological valve to control oxygen in the soil. Roots supply exudates to glue soil particles together to form macroaggregates and supply food for microbes. Source: Hoorman et al., 2009. Ohio State University
Diverse Cover Crops: Winter pea and radish Nodules
Soil Health/Healthy Soil - What is It? The continued capacity of the soil to function as a vital living ecosystem that sustains plants, animals, and humans Nutrient cycling Water (infiltration & availability) Filtering and Buffering Physical Stability and Support Habitat for Biodiversity Grower Value: Improving soil health reduces the risk of soil compaction plus increases the recovery of the soil to compaction.
New Tools for Identification As-planted data Imagery Machine data
Tractor tire paths visible after field cultivator Hidden variables impacting crop development and yield COMPACTION (soil health component) Question: How do we identify and quantify?
As-Planted Data: Row-Unit Ride Quality Map In-Cab Display Feedback Producer Value 1) Identify and correct equipment issues immediately.; 2) Execute prescriptions; 3) Identify soil characteristics (e.g. clods, trafficked areas)
1.5 months after planting
Question: How do we identify and quantify? Answer: Using Imagery & machine data. Decision --- ½ day too early on field cultivator!
Machine Data CAN messages, Health, etc. Effective tool to evaluate operating costs and capacity --- FUEL USAGE, UPTIME vs. DOWNTIME, ENGINE LOAD.
You can't manage what you don't measure! (W. Edwards Deming)
Managing to Avoid Compaction Problems Controlled Traffic (GPS guidance) Bigger tires, lower inflation pressure Variable inflation pressure (correct psi for in-field and on road) More axles, less weight/axle Rubber tracks Continuous No-Till Cover Crops
Digital Agriculture Providing solutions to meet world demand John Fulton Fulton.20@osu.edu 334-740-1329 @fultojp Ohio State Precision Ag Program www.ohiostateprecisionag.com Twitter: @OhioStatePA Facebook: Ohio State Precision Ag