|In medieval times, farming
was usually based on an 'open field' system, each village usually
having at least three unfenced areas surrounding the village.
These would be divided into strips cultivated by the villagers,
often working as 'serfs' to the landowner. Wheat or rye would be
grown in one field, barley or oats in the second, and the third
would be left uncultivated or fallow. In the days before
artificial fertilisers, the livestock would be the source of
manure to replenish the nutrients in the soil. However, this
rotation only cropped two thirds of the cultivated land, with the
crops rotating by one field each year.
|When Charles Townshend
(1674 -1738) retired from politics in 1730, he devoted his time to
agricultural improvements. Although turnips were grown in Britain,
Townshend became a keen advocate for including them within a
rotational system. He introduced a Flemish system, later developed
as the 'Norfolk four-course rotation', and also leading to him
acquiring the name of 'Turnip' Townshend. His rotation had clover,
wheat, turnips and barley as the four crops grown in rotation, the
clover and turnips removing the need for a fallow area. These
additional crops also provided fodder for livestock during the
winter, an important factor where large flocks of sheep were
common. Previously many of the livestock had to be slaughtered
because of the lack of winter fodder.
|The four plots growing in
the display cage represent the crops that would be grown in
rotation in the fields included within a Norfolk four-course
- Clover, a legume, has nitrogen fixing nodules on the roots.
When ploughed in, the nitrogen becomes available for the next
- Wheat, utilising the nitrogen released by breakdown of the
- Turnips, lifted and stored as winter fodder, or sheep
allowed to feed on the crop and manure the soil.
- Barley, utilising the nutrients added by the sheep dung.
information on crop rotation
is available as a downloadable 'pdf' file.