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Competency Area 5: Soil conservation AEM

PO 49. Describe the basic components and workings of tillage systems, and understand their agronomic and environmental benefits.

  1. Plow-till
  2. No-till
  3. Mulch-till
  4. Ridge-till
  5. Zone tillage

Distinctions are made between primary and secondary tillage.

Primary tillage is usually the deepest operation in the system, which loosens and fractures the soil to reduce soil strength, invert and cover previous crops or weeds and to bring or mix residues and fertilizers in the tilled layers. The implements for primary tillage include moldboard, chisel, and disk plows, heavy tandem, offset and one-way disks, subsoilers and heavy-duty, powered rotary tillers.

Secondary tillage is used to kill weeds, cut and cover crop residues, incorporate herbicides, and prepare a well pulverized seedbed. Secondary tillage tools include light- and medium-weight disks, field cultivators, row cultivators, rotary hoes, drags, powered and unpowered harrows or rotary tillers, rollers, ridge- or bed-forming implements, and numerous variations of those.