EXTENSIVE COMMERCIAL AGRICULTURE IN NORTH AMERICA
Location:
The largest concentration is found on the Great Plains of Kansas,
Oklahoma, Colorado, Wyoming, Montana, North Dakota and South Dakota;
and on the Canadian prairie provinces of Alberta, Saskatchewan and
Manitoba.
Main Features:
Extensive commercial farms are huge, highly mechanised arable farms
which tend to specialise on one main crop such as wheat. Relatively low
yields are compensated for by the huge areas under cultivation.
Physical Advantages:
 Growing season is long enough to give the required 90 days
 Warm summers and long hours of sunshine are ideal for cereal
production
 Precipitation occurs mainly in the growing season
 Black chernozem soils are deep and fertile
 Land is relatively flat – aids mechanisation and transportation
 Severe winter frosts help to break up soil ready for planting
 Warm Chinook wind helps to melt winter snow.
Disadvantages:
 Periods of drought
 Hail and early cold snaps can ruin crops
 Summer tornadoes (‘tornado alley’)
 Once natural vegetation is removed the soil is easily eroded.
History:
 During the 19th Century, the pacification of the Sioux Indians and
the westward extension of the railroads allowed for the large scale
settlement of the Great Plains by settlers from the eastern states
and from Europe.
 The geometric appearance of the present day landscape was
created by surveyors before the land was settled. Land either side
of the railroad was surveyed and laid out into townships, each
consisting of 36 sections with 256 hectares in a section. Settlers
were each given 64 hectares (a quarter section) of free land
providing they built a house on it and cultivated their holding.

Cultivation of the Great Plains was successful for a time but long
periods of drought and inappropriate farming techniques caused
accelerated soil erosion during the 1920s and 1930s. The southern
states of Kansas and Oklahoma were the worst affected and this
area was nicknamed ‘the Dust Bowl’. Massive rural depopulation
resulted.
Changes:
 Most of the early quarter section homesteads did not survive
because of recurrent droughts. Surviving farmers were allowed to
increase their holdings to a full section (256 hectares) by
amalgamating with abandoned farms. Larger units are more
profitable (economies of scale / “agribusiness”).
 Improvements in agricultural technology such as new steel ploughs,
reapers and binders, pumps and windmills. Also new strains of fastgrowing spring wheat.
 Increased use of chemical fertilisers and pesticides has led to an
increase in crop yields but also environmental consequences e.g.
nitrates in water supplies.
 Large crop yields have led to overproduction and surpluses.
Federal government payments are given to farmers to cut back on
production.
 New, modern farm buildings (grain stores, silos, machinery sheds)
are often criticised for being eyesores.
 Decline in workforce needed on farms has led to rural depopulation
and a smaller demand for services in the rural economy. This has
led to school closures etc.
 Periods of drought and soil erosion continue to pose a threat but
are tackled more effectively today by contour ploughing, strip
cultivation and shelter belt planting.