Geoscience Reference
In-Depth Information
labour. Some were in response to major climatic shifts like the period in the 8th cen-
tury when the north coast of Scotland exported grain to Scandinavia. Few changes,
until the 18th century, were due to technical invention or scientific insight.
A
BRIEF HISTORY
For perhaps 2000 years, agriculture maintained simple crop rotations with a fallow
every alternate year or one in three on the better soils. This routine became incor-
porated into the medieval 3-field system which also introduced ridge-and-furrow, as
described in the last chapter. During the 14th and 15th centuries, there was a general
swing to pasture and sheep farming when much arable land would have gone down
to permanent grass. Subsequently, some of this land went under the plough again to
participate in the 4-course rotation introduced by 'Turnip' Townshend in 1730. This
rotation was developed on the lighter soils of East Anglia, and alternated turnips and
clover between corn crops. It was widely adopted for it allowed continuous cropping
for the first time while still maintaining soil fertility. Sheep were folded onto the root
crops in winter and onto the clover in summer. On the heavier Midland soils, the
4-course rotation often retained one fallow year, and used beans or peas in place of
clover. Sheep were kept separate on the permanent pasture.
This farming system lasted for the next 150 years, until corn prices fell in the ag-
ricultural depression of the 1880s. Grass as a rotational crop then became widely used
as a soil conditioner, and the Midlands, which had become the corn belt of England,
became predominantly grass again.
Meantime, land drainage schemes had opened up new areas of fenland to ag-
ricultural use: 300,000 acres around Ely and 95,000 acres around Whittlesey - the
South and Middle Bedford Levels - in the first half of the 17th century; 10,000 acres
in Holland and Kesteven in the mid-18th century; 20,000 acres of Kings Sedgemoor
in Somerset in the early 19th century. As the peat dried out it shrank, and natural
drainage was no longer possible so hundreds of wind-driven scoop mills were built
between Lincoln and Cambridge to improve the area. In one of Cobbett's rural rides in
1830, he described a fenland scene as “twenty thousand acres of land around, covered
with fat sheep, or bearing six quarters of wheat or ten of oats to the acre without any
manure” (6 quarters/acre is about 0.2 t/ha). The introduction of steam-driven pumps
improved still further the arterial drainage in the Fens. The last great mere at Whittle-
sey was drained by a centrifugal pump demonstrated at the Great Exhibition in 1851.
This area was thus transformed in a few years from agriculturally valueless wastes -
the haunts of bittern and wildfowl - to some of the richest land in the country.
A little earlier, in 1831, James Smith published his
Remarks on Thorough Drain-
ing and Deep Ploughing.
His attention was focussed on the clay lands as he realized
