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The Epic Interactive Encyclopedia 1997
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1992-09-02
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Ambiguous term for several different types of
crop; in agriculture, it refers to turnips,
swedes, and beets, which are actually
enlarged hypocotyls and contain little root,
whereas in trade statistics it refers to the
tubers of potatoes, cassava, and yams. Roots
have a high carbohydrate content, but their
protein content rarely exceeds 2%.
Consequently, communities relying almost
exclusively upon roots may suffer from
protein deficiency. Potatoes, cassava, and
yams are second in importance only to cereals
as human food. Food production for a given
area from roots is greater than from cereals.
In the mid-1980s, world production of
potatoes, cassava, and yams was just under
600 million tonnes. Potatoes are the major
temperate root crop; the major tropical root
crops are cassava (a shrub that produces
starchy tubers), yams, and sweet potatoes.
Root crops are also used as animal feed, and
may be processed to produce starch, glue, and
alcohol. In England the earliest root crops
were grown about 1650.