tillage

Tillage is a farming practice that involves mechanical manipulation of the upper layer of soil to prepare a seedbed, control weeds, incorporate crop residues, and influence soil properties. It ranges from shallow cultivation to deep inversion and may use a variety of implements powered by animals or machines. Tillage can modify soil structure, moisture dynamics, and biotic conditions in the field.

Tillage is commonly categorized as primary tillage, which disturbs the soil to a depth that disrupts compaction and buries residues, and secondary tillage, which further refines the seedbed and manages surface trash. Primary methods include plowing with moldboard or disk plows, chisel plowing, and moldboard alternatives. Secondary tillage includes harrowing, field cultivating, and finishing passes.

Conventional tillage typically involves significant soil disturbance with frequent inversion; reduced or minimum tillage lowers disturbance and preserves more residue on the surface. No-till farming minimizes or eliminates soil disturbance, relying on herbicides or mechanical means to manage weeds. Conservation tillage emphasizes maintaining soil cover and reducing erosion through residue retention.

Equipment used in tillage includes plows, harrows, cultivators, rototillers, and chisels, often mounted on tractors. The choice of tool depends on soil type, crop, residue level, and objectives such as weed control, residue incorporation, or seedbed finishing.

Environmental considerations include effects on soil organic matter, structure, and erosion risk. Tillage can increase carbon release and reduce soil moisture retention if overused, but reduced-tillage and no-till systems aim to mitigate these impacts. The practice also influences weed ecology and pest dynamics and is a major factor in sustainable agriculture debates.