Moldboard

A moldboard is the curved metal plate on a plow that turns or inverts soil as the implement moves through the field. It forms a furrow and flips the loosened soil over, burying crop residues and weeds and mixing the upper soil layer.

Operation and function: The plow’s share cuts the soil, and the moldboard guides and inverts the slice as the tool moves forward. The shape and angle of the moldboard determine the depth of plowing and the degree of inversion. Together with other plow components such as the coulter (a cutting wheel or blade), the moldboard helps create a uniform furrow and soil turnover.

Design and varieties: Moldboards are part of moldboard plows, which come in various shapes (for example ogee, tulip, or straight) that influence soil handling in different soils and moisture conditions. The curvature and tilt can affect how cleanly the soil is inverted and how much residue is buried versus left on the surface.

History and use: The concept of turning soil with a curved plate evolved with the development of iron and steel plows in the 18th and 19th centuries. The moldboard plow became widely adopted in agricultural mechanization, with improvements in steel construction contributing to efficiency, especially in heavy or compact soils. Its use facilitated cultivation of large-scale landscapes such as prairie regions.

Contemporary role: In modern agriculture, moldboard plows are less common in regions emphasizing conservation tillage, soil health, or minimal disturbance, where disc or chisel plows may be preferred. They remain useful where complete inversion and burial of residues are desired or required by farming practices.