How a plough works

A plough is made of many parts

In front of the plough body may be a coulter, this is either a sharp disc or a knife set to make a vertical cut in line with the flat side of the plough. Coulters are not needed in light arable land that was last ploughed a year ago, they are vital when turning over a tough grass sward.

To help bury turf a skimmer may be fitted just behind the coulter. This is a mini-mouldboard that trims a shallow slice off the top and tucks it in so that not even the edge of the turf will be visible at the surface after the plough has passed.

The plough point makes a horizontal cut at a preset depth and a slice of soil is lifted onto the mouldoard which turns it over.

Everything must be in line, sharp and firmly mounted or the tractor will have extra work to do.

Setting up the plough and tractor

The plough must be carefully aligned with the tractor. There must be exactly one furrow width between the inside of the rear right-hand wheel of the tractor and the first ploughshare.

Initially the plough must be level with the tractor but after a couple of passes the ploughed strip will be wide enough that the tractor's wheel will be running in the trench from which the last cut was taken. The plough must now be adjusted to run level with the land surface while the tractor stays down on one side for the rest of the job.

Next: Reversible ploughs, ploughing in 'lands.'