Tillage

Tillage operations in numerous forms have been practiced from the very inception of developing plants. The primitive man utilized tools to disorder the soils for placing the seeds. The word tillage is derived from ‘Anglo-Saxon’ words Tilian and Teolian, meaning ‘to plough and prepare the soil for the seed to sow, to cultivate and to raise crops’. Jethro Tull, who is considered as the father of tillage suggested that thorough ploughing is necessary so as to make the soil into fine particles.

• Etymological meaning- stirring actions or beginning for improving the physical condition of the soil or make it suitable for cultivation
• Tillage – manual or mechanical manipulation of the soil to provide a medium for proper crop establishment and growth.

Objectives of tillage:

The main objectives of tillage are:

• Seedbed Preparation – provide an optimum environment for seed germination and subsequent growth, temperature, moisture, aeration, seed-to-soil contact
• Incorporating and mixing of organic matter and soil amendments like crop residues, lime, fertilizers, and pesticides.
• To produce a good seed that helps in seed germination.
• Creating conditions in suitable soil for better crop growth.
• To accomplish these objectives, the soil is disturbed/opened up and turned over. 
• To conserve water and soil, prevent erosion, conserve precipitation, improve infiltration, and the shape of the soil.
• Provide proper contact with seed-soil to allow water flow to the seed and seedling roots.
• To increase the soil's ability to absorb more rainwater.
• To remove the hardpan and to increase the soil depth.
• To control the weeds effectively and to eliminate ground pests.

Types of tillage:

1. Preparatory tillage

• Primary tillage(Deep Tillage, Sub-Soiling, Year-Round Tillage)

• Secondary tillage

• Layout of seedbed

2. After cultivation (Inner tillage)

1. Preparatory tillage

Preparatory tillage refers to the operations of tillage that is done to prepare the field for growing crops. It involves deep opening and loosening of the soil, which creates the desired tilth and can uproot weeds and crop stubble when the soil is in working condition.

• Primary tillage

The operation of tillage that is done to bring the land under cultivation after harvest is called primary tillage or ploughing. Ploughing is the opening of compact soil with the help of various ploughs. Country plough, moldboard plough, bose plough, tractor, and power tiller drawn implements are used for primary tillage. Inverts or shatters soil 6-14 inches deep; leaves the soil rough, loosen and aerate surface layer, incorporating fertilizer, cover plant residues.

Deep tillage: 

Deep ploughing turns out large-sized clods.

Sub-soiling:

break hardpans may be present in the soil which restricts the root growth of crops.

Year-round Tillage:

Tillage operations carried out throughout the year.

• Secondary Tillage

The tillage operations that are done on the soil after primary tillage to bring good soil tilth are called secondary tillage. Depth is 2-6 inches deep, prepare a final seedbed, level, and firm soil, pulverize soil for seed-to-soil contact, control weeds. 

• Layout of Seedbed

This is additionally among the components of preparatory tillage. After the preparation of the seedbed, the field is properly distributed for irrigation and planting or planting seedlings.

2. After cultivation/Tertiary tillage:

The tillage operations that are done in the standing crop after the sowing or planting and prior to the harvesting of the crop plants is known as after tillage. Any cultivation operation is done after the emergence of crop seedlings, placement of fertilizers, weeding, intercultural hoeing, pulverization of soil between rows for mulching earthing up.

Tillage systems

Tillage systems are sequences of operations that manipulate the soil to produce a crop. Operations include tillage, fertilization, planting, harvesting, pesticide application, and chopping or shredding of residues.

• Conventional tillage: Normal primary and secondary operations – varies from region to region
• Clean Tillage: Leave little or no residue on the soil surface
• Mulch Tillage: Leave the residue to reduce soil/water loss
• Conservation Tillage: Leave >30% residue cover on the soil surface.
• Minimum Tillage: Systems that use the least amount of tillage required.
• Reduced Tillage: Use more or less energy-efficient tasks.
• Full-width Tillage: Tillage of entire field surface.
• Strip-Tillage: Tillage of strips, leaving undisturbed strips.
• No-Till: Seed planted directly into previously undisturbed soil.
• Ridge Tillage: Ridges/furrows established & maintained throughout the year.