Types Of Tillage On The Basis Of Seasons

TYPES OF TILLAGE

1. On Season Tillage: It is done during the cropping season (June–July or Sept.–Oct.).

2. Off Season Tillage: It is done during fallow or non-cropped season (summer).

3. Special Types of Tillage: It is done at any time with some special objective/purpose.

On Season Tillage

Tillage operations done for raising the crops in the same season or at the onset of the crop season are called as on season tillage. They are,

A. Preparatory Tillage

It refers to tillage operations that are done to prepare the field for raising crops.

It is divided into three types viz.,

(i) primary tillage,

(ii) secondary tillage, and

(iii) seed bed preparation.

(i) Primary tillage – The first cutting and inverting of the soil that is done after the harvest of the crop or untilled fallow, is known as primary tillage. It is normally the deepest operation performed during the period between two crops. Depth may range from 10–30 cm. It includes ploughing to cut and invert the soil for further operation. It consists of deep opening and loosening the soil to bring out the desirable tilth. The main objective is to control weeds to incorporate crop stubbles and to restore soil structure.

(ii) Secondary tillage – It refers to shallow tillage operation that is done after primary tillage to bring a good soil tilth. In this operation the soil is stirred and conditioned by breaking the clods and crust, closing of cracks and crevices that form on drying. Incorporation of manures and fertilizers, leveling, mulching, forming ridges and furrows are the main objectives. It includes cultivating, harrowing, pulverizing, raking, leveling and ridging operations.

(iii) Seed bed preparation – It refers to a very shallow operation intended to prepare a seed bed or make the soil to suit for planting. Weed control and structural development of the soil are the objectives.

B. Inter Tillage/Inter Cultivation

It refers to shallow tillage operation done in the filed after sowing or planting or prior to harvest of crop plants i.e., tillage during the crop stand in the field. It includes inter cultivating, harrowing, hoeing, weeding, earthing up, forming ridges and furrows etc. Inter tillage helps to incorporate top dressed manures and fertilizers, to earth up and to prune roots.

Off Season Tillage

Tillage operation is done for conditioning the soil during uncropped season with the main objective of water conservation, leveling to the desirable grade, leaching to remove salts for soil reclamation reducing the population of pest and diseases in the soils. etc. They are:

(a) Stubble or Post harvest tillage – Tillage operation carried out immediately after harvest of crop to clear off the weeds and crop residues and to restore the soil structure. Removing of stiff stubbles of sugarcane crop by turning and incorporating the trashes and weeds thus making the soil ready to store rain water etc., are the major objectives of such tillage operations.

(b) Summer tillage – Operation being done during summer season in tropics to destroy weeds and soil borne pest and diseases, checking the soil erosion and retaining the rain water through summer showers. It affects the soil aggregates, soil organic matter and sometimes favour wind erosion. It is called as Kodai unavu in Tamil Nadu state.

(c) Winter tillage – It is practiced in temperate regions where the winter is severe that makes the field unfit for raising crops. Ploughing or harrowing is done in places where soil condition is optimum to destroy weeds and to improve the physical condition of the soil and also to incorporate plant residues.

(d) Fallow tillage – It refers to the leaving of arable land uncropped for a season or seasons for various reasons. Tilled fallow represent an extreme condition of soil disturbance to eliminate all weeds and control soil borne pest etc. Fallow tilled soil is prone to erosion by wind and water and subsequently they become degraded and depleted.

Special Types

Special type tillage includes

(i) Subsoil tillage (sub soiling) is done to cut open/break the subsoil hard pan or plough pan using sub soil plough/chisel plough. Here the soil is not inverted. Sub soiling is done once in 4–5 years, where heavy machinery is used for field operations and where there is a colossal loss of topsoil due to carelessness. To avoid closing of sub soil furrow vertical mulching is adopted.

(ii) Levelling by tillage – Arable fields require a uniform distribution of water and plant nutrition for uniform crop growth. This is achieved when fields are kept fairly leveled. Levellers and scrapers are used for levelling operations. In leveled field soil erosion is restricted and other management practices become easy and uniform.

(iii) Wet tillage – This refers to tillage done when the soil is in a saturated (anaerobic) condition. For example puddling for rice cultivation.

(iv) Strip tillage – Ploughing is done as a narrow strip by mixing and tilling the soil leaving the remaining soil surface undisturbed.

(v) Clean tillage – Refers to the working of the soil of the entire field in such a way no living plant is left undisturbed. It is practiced to control weeds, soil borne pathogen and pests.

(vi) Ridge tillage – It refers to forming ridges by ridge former or ridge plough for the purpose of planting.

(vii) Conservation tillage – It means any tillage system that reduces loss of soil or water relative to conventional tillage. It is often a form of non-inversion tillage that retains protective amounts of crop residue mulch on the surface.

The important criteria of a conservation tillage system are:

(a) presence of crop residue mulch,

(b) effective conservation of soil and water,

(d) maintenance of high and economic level of production (refer section 7.10 of this chapter).

(viii) Contour tillage – It refers to tilling of the land along contours (contour means lines of uniform elevation) in order to reduce soil erosion and run off.

(ix) Blind tillage – It refers to tillage done after seeding or planting the crop (in a sterile soils) either at the pre-emergence stage of the crop plants or while they are in the early stages of growth so that crop plants (cereals, tuber crops etc.) do not get damaged, but extra plants and broad leaved weeds are uprooted.