How Air Pressure Impacts Soil Compaction in Harvest Applications

Soil compaction is the decrease in the porosity of the soil. When compaction is present, air, nutrients and water can’t get into the soil to nourish the plant.

Compaction also “decreases water infiltration in the soil and increases water runoff, which can increase soil erosion and gullies in the field,” says Dave Paulk, manager, field technical services, BKT USA Inc. “It restricts root growth and decreases yield. Roots can’t penetrate the soil and develop a healthy root system. This can lead to an uneven stand of plants and stunted growth.”

Air pressure creates ground bearing pressure, says Paulk. “The higher the air pressure used, the higher the ground pressure. It’s important to use proper tire inflation pressure for the weight. By running correct air pressures to carry the weight, soil compaction is minimized. This can be achieved by running radials. Radial tires exert one to two pounds of pressure higher than their air pressure. For example, a tire running 10 psi will exert about 11 to 12 pounds per square inch of ground pressure.

“Choosing the right tire is essential. Less air pressure is needed for IF/VF tires to carry the same load as the standard tire. Wider tires and duals can be run at lower air pressures to help minimize compaction. Running too much air pressure creates more soil compaction and increases slippage to the point where more fuel is burned. It also causes impact breaks more easily in tires. For harvest operations, IF/VF CFO tires can carry heavier loads at slow speeds without increasing air pressure.”

According to Paulk, benefits of helping farmers maintain proper air pressure levels include better traction, less slippage for better use of power, enhanced fuel economy and the general minimization of tire-related problems. “The bigger the footprint, the more area the weight is spread over,” he says.