Plough

How it works

Each plough body has a share, a flat blade that slices sideways under the soil, and a mouldboard, the curved plate behind it that lifts the cut strip (the furrow slice) and rolls it over. A flat landside plate runs against the wall of the furrow and stops the body being pushed sideways, which keeps the furrow width even. These parts bolt to a central casting called the frog.

Ahead of each body a disc or knife coulter can cut the furrow wall cleanly, and a small skimmer shaves off a strip of surface trash and drops it into the bottom of the furrow so it is buried rather than left poking out. Depth is held by a depth wheel at the back and the tractor's linkage. The shape of the mouldboard matters: general purpose bodies suit work around 20 cm deep, semi-digger bodies around 25 cm and digger bodies 30 cm or more.

Main types

• Conventional (one-way) plough: The bodies only throw soil to one side, so the field is ploughed in strips called lands, leaving ridges and open furrows where the lands meet. Simple, light and cheap, and still common on older and smaller tractors.
• Reversible plough: Two sets of bodies sit back to back, one turning soil right and one left. A hydraulic ram rolls the frame over at each headland, so every furrow falls the same way and the field is left level with little idle running.
• Semi-mounted plough: The front hangs on the lower links and the rear rides on its own wheel, which lets makers build ploughs of seven to twelve furrows that would be far too heavy to lift on the linkage.
• Vari-width plough: The working width of every body can be changed hydraulically from the cab, often between about 30 and 55 cm per furrow, to suit soil, speed and tractor power.
• Chisel and disc ploughs: A chisel plough loosens soil with deep tines without turning it over, leaving residue on top. A disc plough uses large concave discs to cut and throw the soil and copes with hard or trashy ground.

Hooking it up to a tractor

Most ploughs are mounted on the three-point linkage, so lift capacity matters as much as horsepower. As an example, Kverneland's five-furrow 2300S weighs 1,630 kg and needs about 5,100 kg of lift, with its headstock rated for 230 hp. A reversible plough needs a double-acting spool valve for the turnover ram, and more spools if the width, depth wheel or top link are hydraulic. A plough takes no PTO drive; all the work is done by pulling.

A short history

Ploughed fields go back to around 2800 BC in the Indus valley, and iron mouldboard ploughs were in use in Han China in the first and second centuries AD. In 1730 the Rotherham plough, linked to Joseph Foljambe, became the first commercially successful iron plough, and from 1789 Robert Ransome's chilled cast shares were sold as self-sharpening. John Deere's steel plough of 1837 handled sticky prairie soils. Steam cable ploughing (see the balance plough) took over big fields in the later 1800s before tractors replaced it in the twentieth century.

Buying and care tips

• Check the wearing parts: Look at points, shares, mouldboards and landsides for thin metal and holes. Hard carbide tipped parts cost more but can last many times longer in abrasive soils.
• Stone protection: Shear bolts are cheap but stop work when one breaks; auto-reset legs with springs let each body ride over a stone and drop back in. Many leaf-spring systems can be made stiffer by adding leaves.
• Headstock and turnover: Rock the plough on the linkage to feel for worn pivots, and check the turnover ram and hoses for leaks.
• Clearance and bodies: Good underbeam and interbody clearance stops trash and cover crops blocking. Match the body type to your soil and working depth, and check the front furrow width suits your tractor's tyres.
• Set skimmers properly: Skimmers set too deep waste power; too shallow and trash is left showing. Adjust them before blaming the plough for a poor finish.

Questions people ask

What is the difference between a reversible and a conventional plough?

A conventional plough turns soil one way only, so you plough in lands and leave ridges and open furrows. A reversible plough has left and right bodies and flips at each end, so you can plough up and back and leave a level field.

What does a skimmer do on a plough?

A skimmer is a small mouldboard in front of the main body. It peels off surface trash and drops it into the furrow bottom so it is buried completely.

How deep does a plough work?

Most ploughing is done at about 15 to 25 cm. Digger bodies can go deeper, to 30 cm or more, but deeper work needs more power and can bring up poorer subsoil.

What is a vari-width plough?

A plough whose furrow width can be changed, usually hydraulically from the cab, so the operator can match the cut to conditions and tractor power.

Related equipment

Sources

1. Plough (Wikipedia)
2. On test: Kverneland's new five-furrow 2300S plough (Farmers Weekly)
3. Kverneland PW semi-mounted reversible plough (Kverneland)

Last checked 2026-11-01

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