Ever wondered what combine harvesters do and how they work? Adam Henson explains
The sight of a massive combine harvester sweeping through acres of ripe, golden wheat is one of the most impressive things you can see in the fields of Britain. It doesn’t matter how many times you witness these monster machines at work, the way they slice through the crop still makes you stop and stare.
What does a combine harvester do?
Although commonly called combine harvesters, farmers refer to them purely as combines. The name comes from the simple fact that the machine ‘combines’ three different tasks; reaping, threshing and winnowing. Reaping is the cutting and collecting of the crops; threshing loosens the grain from the dry casing around the seed; winnowing then divides the grain that’s needed from the scaly plant material that isn’t, so it literally separates the wheat from the chaff.
How does a combine harvester work?
Machines vary, but the basic mechanics are the same and a typical combine works in a number of individual stages. First, as the combine travels forwards, the crop is gathered in by the header.
The crop is drawn over the cutting blades by the rotating pick-up reel at the front. The cut crops are then elevated into the threshing cylinder or drum, which shakes the grain from the stalk. The grain is then sieved and collected in a storage tank.
When the tank is full, the grain is carried by an elevator up through a side pipe (or unloader) and into a trailer that has pulled up alongside. A fan blows the chaff out of the sieves while the straw can be collected and bailed.
You could argue that the combine is the most important labour-saving device ever invented. It has revolutionised the gathering of crops worldwide, making harvest simpler, swifter and more cost-effective. It has also changed the face of farming forever – economically and socially. No longer are large teams of workers employed in the fields in the late spring and summer. Our farming forebears would be familiar with entire villages working for days on end with several generations of the same family helping to bring home the harvest.
Today we don’t need an army of reapers, rakers and threshers and the number of employees has shrunk dramatically; at the same time mechanisation has eliminated the poor working conditions and child labour that were commonplace.
Before combines, crops were cut by hand when they were half ripe. The seed head was kept intact on a long stem which meant that they could be bound together into sheaves and stacked in the field to ripen off. But since the 1830s when the first rudimentary horse-drawn combines appeared, things have gradually changed. So much so that you can think of a modern combine as a factory on wheels.
How much are combine harvesters?
Perhaps it’s no surprise that the most up-to-date models come with a hefty price tag. A new one could set you back £250,000 or more and even second-hand combines cost in excess of £100,000.
To help spread this expensive cost we work with a neighbour in a Joint Venture Farming operation where the machines are shared and used on both farms, as well as being used for contracting work. The arable area we now farm collaboratively totals 3,000 acres or 1,200 hectares.
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