My John Deere Steel Plow Damages Soil

Research

• David Montgomery, professor of earth and space sciences at the University of Washington, authored a study identifying plowing as the cause of soil erosion. Soil erosion takes place when the rate of soil depletion is greater than the rate of soil creation. “Soil loss through conventional agriculture is in a range of 10 to 100 times greater than the rate at which soil is created,” Montgomery has noted.

Loss of Soil Fertility

• Long-term fertility is damaged by the use of steel plows to turn over the soil. Its organic matter is exposed to the atmosphere and oxidized into carbon dioxide. Carbon dioxide emissions are a major cause of global pollution problems. Deeply tilled soil does not retain water efficiently because its organic matter content has been eroded. Soil microorganism populations are also reduced by conventional plowing practices.

Disc Plow Method

• The University of Washington study concludes that replacing the conventional steel plow with the rotating disc method preserves vital topsoil. A disc plow cuts crop residue off above the soil, leaving it to decompose and add to soil tilth. Crop roots are left in the ground to hold soil in place during rain and wind. A chisel plow is then used to create a narrow, shallow furrow for seed planting and fertilizer application.

No-Till Agriculture

• No-till agricultural practices are recommended by the Fairfax County, Virginia Soil and Water Conservation District as a way to preserve soil viability and increase profitability. Non-plowed soil retains organic matter, which means “more fertility, less fertilizer, and higher yields.” Crop rotation and green manure crops are methods used to control weeds in the no-till system of farming.