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A Brief History of The Plough
by Alan Jones, Tillage Product Manager, Kverneland (UK) Ltd.
Farming is perhaps the oldest industry in the World. Historians are generally
agreed that the earliest implement was probably a crude pointed bent stick or
tree branch which was used to stir the soil surface. In affect a hand held hoe
in which the user scratched at the earth to form a tilth in which corn could be
sown. Early mans struggle for survival became closely linked to the success of
his crops and therefore he cultivated more land in order to grow more corn to
sustain his life. It soon became apparent that the more the soil was tilled the
better the germination and crop quality.
 Man
continually strived to become more efficient and those hand held hoes soon
developed into simple ploughs, well before the early Egyptians over 4000 years
ago. These primitive ploughs were eventually pulled by oxen, camels and even
elephants and it is said in some instances women were also used. Animals enabled
the land to be tilled more easily and faster, thus more food was produced.
The primitive plough made an open shallow furrow by pushing the soil away to
either side, rather than inverting as we know today. The ancient Egyptians made
considerable advances in its design albeit primitive to our standards. They also
succeeded in growing many crop varieties in their dry arid climate by devising
complex irrigation systems. As depicted on many of their monuments, the
development of the plough from hand held sticks to implements pulled by
animals, put them far ahead compared to other civilisations. However, the Greeks
were not so far behind and later developed Egyptian ploughs fitted with wheels.
These were known as a crooked ploughs because the beam curved forwards to the
draft animal. The fitment of wheels provided far greater control and
manoeuvrability. Oak was used for the share beam, elm the draught beam and iron
for the shares. Iron at that time was very precious, so plough share metal was
used and shaped into weapons in times of war. The Romans however, were very
efficient with their conquering advances, but their ploughs were simple and
crude in design. Although there had been enormous advances from the simple
stirring sticks, for these early ploughs to produce well tilled soil, the land
would have to be cross ploughed at right angles to the first operation to ensure
all the land was well prepared for sowing.
In our own country following the Romans, early British law required every
ploughman to make his own plough, and that no one was entitled to use one unless
they constructed it themselves. The word 'plough' appears to derive from  the
Saxon 'plou' and some of the history records show that even Saxon farmers
fastened their draft animals to ploughs by their horns or even tails to draw the
implement through the soil. This barbaric custom even surviving in parts of
Ireland until the 17th century.
There was little attempt to change the design of the plough until the mid 1600's
with the Dutch being among the first in improving its shape. This change in
shape was soon discovered in Northern England and Scotland with Joseph Foljambe
from Rotherham building and patented a plough having what was described as, the
perfect implement then in use.
 Known
as the Rotherham swing plough, because no depth wheel was used, it was like
ploughs before it, constructed from wood. The difference was that the fittings
and coulter were made of iron and the mouldboard and share were covered with an
iron plate. This new design was considered by all who saw it at work to be more
efficient and lighter to pull than any other kind at that time. For over 30
years this design proved very popular and was used extensively up and down the
country. It was perhaps the first to be factory produced on a large scale.
Man continually experiments to become more 
efficient and in 1763 a Berwickshire man, John Small, first applied mathematical
calculations and science to the mouldboard shape. He experimented with varying
mouldboard curvatures and patterns, eventually producing a universal cast iron
shape that would turn the soil more effectively with less draft, wear and strain
on the ploughman. Over the years this 'Scots Plough' as it was know, was the
beginning of the plough we all know today.
Like our ancestors, we continue to strive for improvement. If we take a look at
plough development over the last 50 years there has been enormous change. Horse
ploughs soon became redundant for more efficient steam units with large multi
furrow balance ploughs, quietly trundling up and down fields with only the sound
of a whistle to indicate a change of ploughing direction.
Using converted horse ploughs, the more manoeuvrable wheeled tractor slowly took
over from steam in the early 1900's and was the start of the format we are all
familiar with today. When Harry Fergurson's 3-point linkage appeared in  1920,
it totally revolutionised implement attachment and machine performance and has
now become the universal norm.
The Last Thirty Years
For most of us the last 30 years is relevant, because we too have witnessed many
changes in plough design, in what is a very small space in time. For example,
the reversible plough now dominates because of its simplicity and ability to
produce level fields. An essential part of modern farming practice, with ever
larger equipment being employed. Sprayers, combines, sugar beet harvesters to
name but a few would not perform to the standards expected unless reversible
ploughs were in use.
Looking closer, we can pick out some major changes in design which have been
necessary to cater for the needs and pressures of farming.
Reversing Mechanism
All ploughs now feature hydraulic turnover systems for indexing and
hydraulic change-over valves for automatic cylinder stroke direction. The old
mechanical lever systems would not be able to rotate today's ploughs, as they
are very much bigger and heavier and often out of balance. Hydraulic reversal is
also assisted further with main frame alignment. This allows the plough frame to
swing in line with the tractor to prevent the rear wheel or bodies from hitting
the ground. It also improves stability and reduces the high forces imposed on
both the plough and tractor.
Wheel Settings
Thirty years ago, if you had a 75hp tractor on the farm it was big
and in most cases only had two wheel drive. We used to operate ploughs with 56
or 60in. tractor wheel 'centre-to-centre' settings - not any more. Modern
tractors feature 4WD, wider wheel equipment and inside tyre settings up to
1800mm to transmit the high horse powers available to the ground. The latest
mouldboard designs fitted with furrow bottom wideners unfortunately struggle to
cope with these wide tyres and do not operate well in all soils. If wider furrow
bottoms are needed, then increases in mouldboard 'throw' are necessary. But,
this has the major disadvantage of considerably increasing draft with poor
mouldboard perfomance in sticky soils.
Front Furrow Width Adjustment
Tractor wheel settings control the plough's front  furrow
width. Therefore, ploughs have to have a means of front furrow width adjustment
to ensure the plough is compatible to the tractor wheel settings. In the days of
conventional ploughs, front furrow width was adjusted by rotating the cross
shaft to enable the plough to be steered either towards the land or work, thus
making the front furrow wider or narrower. Although, some manufactures still use
similar steering systems today by angling the plough frame to land or work, this
is fundamentally wrong, as it can cause the plough or even the tractor to crab,
due to an increase or decrease in landside pressure. The correct way is to move
the whole plough literally sideways at 90° to the direction of travel to change
the front furrow width setting. This is achieved by using a simple slide and
rail system, which provides the result required with very little variation to
landside pressure. It also allows for easy fitment of an hydraulic cylinder for
on-the-move adjustment when working in hilly areas.
Furrow Width
Over the years, furrow widths have increased from as little as 6in.
to over 20in. today. Back in the 1930's, horse and early tractor ploughs
operated with furrow widths of 6 to 9in. a) because of limited power to pull
them, b) horses were still being used extensively on the land. The average width
of a horses foot is around 7in. therefore, when land was ploughed and
subsequently sown, often by hand, onto what is termed oat seed furrows, sown
seed would roll and lay in the 'V' shaped furrow. The ploughing would then be
cross harrowed covering the seeds with soil. Once germinated, the seed would be
in rows 7in. apart, just wide enough for the horses foot to pass while walking
through the established crop.
Frame Design
Early reversible ploughs were constructed from rectangular solid
steel bars bolted together to form 'A' shaped sections to which individual
bodies were  attached.
Using this system on today's large multi furrow ploughs, distortion and poor
body alignment, together with supporting the additional weight would be a major
problem. Modern frames are produced from a one piece box section, heat treated
for strength and to keep weight to a minimum. Manufactures without sophisticated
heat treatment equipment however, use welded fabrications which can be heavy and
impose high forces on the rear of the tractor. A plough frame has to with stand
very high twisting forces, especially when in transport mode and therefore has
to be flexible to absorb the stresses and strains, yet rigid enough to maintain
alignment accuracy.
Furrow Width Adjustment
The majority of early reversible ploughs had furrow widths fixed at
12 or 14in. in size. To improve output efficiency and plough versatility,
furrows had to get wider and capable of being adjusted. This was not only to
suit soil conditions, but to help reduce manufacture and dealer stocking levels.
In the late 70's, plough frames were being introduced with wedges, holes and
parallel linkage to enable the furrow width to be easily changed. As today,
output was the key factor and 16" ploughs began to appear from Europe. Many
times we were told by our seniors, 'you can not plough wider than 14in. Well,
they have been proved wrong, because ploughs are now capable of operating at
over 20in. This was not possible without the development of a new mouldboard
shape to allow for wider furrows and faster operation. With a new mouldboard
design, the patented Vari-Width system soon became popular because of its high
output efficiency - more acres a day.
Plough Clearance
85cm (33.5in.) interbody and 70cm (27.5in.) underbeam clearances or
above is generally accepted as adequate for UK surface trash conditions, yet
thirty years ago we were using ploughs with as little as 20in. between bodies
and 17in. underbeam. These early ploughs just would not perform at today's
speeds in excess of 6mph and with large amounts of surface residue left over
after harvest.
Plough Protection
No more rigid plough legs as in the past. All the latest ploughs
can be equipped with either shear bolts or auto-reset systems to protect against
rocks and occasional obstructions. A must now because we are using very high
horse  powered
tractors at faster operating speeds. Not forgetting, ploughs are longer and
heavier today and do not 'jump' over obstacles as in the past - if you were
lucky! Modern steels play an important part too, because they have greater
resistance to wear and can operate under tougher conditions and at higher speeds
without breaking. The old chilled cast iron shares are items of the past and
gone forever.
This is a very short account of our past and we all know life does not stand
still. Development will always continue into eternity, with man trying to find
the ultimate solution in food production for his survival. Modern plastics or
similar, together with electronics and automatic machinery that think as they
operate will be our future. What is revolutionary today will inevitably be
overtaken by science tomorrow. Despite what the critics may say, we can rest
assured, the plough is here to stay.
Kverneland (UK) Ltd, Walkers Lane, Lea
Green, St. Helens, Merseyside, WA9 4AF
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