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66 Earth

FIND OUT MORE. Agricultural Revolution 412 • Early Farming 364–365 • Genetic Engineering 210–211 • Southeast Asia 270–271

WHAT ARE STAPLE FOOD CROPS?

Staple foods form the main part of people’s daily diet.

They include the cereal crops wheat, maize (sweetcorn),

and rice. Wheat is eaten by around 35 per cent of the

world’s population every day. The grain is eaten

whole or ground into flour, which is then

used to make bread or pasta. Maize is

mainly grown in tropical and

subtropical countries. It is eaten

as a vegetable, ground into

flour or cornmeal,

or used to make

cooking oil.

WHAT IS ORGANIC FARMING?

Many farmers spray fields with chemical pesticides

and use chemical fertilizers to protect and enrich their

crops. Organic farmers prefer to use natural farming

methods. They enrich the soil with manure, compost,

or seaweed, and use pest-eating insects or

companion planting (for example, planting

onions with carrots to reduce such pests

as carrot-fly). Organic farmers also

allow pigs and chickens to roam

in fields or yards instead of keeping

them in crowded pens or cages.

Thousands of years ago, people began farming the land

to grow cereal crops, such as wheat, and rearing animals

for their meat, milk, and other products. Today, many

farmers use modern techniques and equipment

to produce bumper crops.

WHERE IS RICE GROWN?

Over 90 per cent of the world’s rice is grown in Asia

and eaten by the people living there. Rice is also

grown in the United States, mainly for export. In the

United States, growing rice is highly mechanized. In

Asia, the work of sowing, planting out the seedlings,

and harvesting is usually done by hand.

WHICH KINDS OF ANIMALS ARE DOMESTICATED?

Middle Eastern farmers began rearing herds of sheep

and goats around 10,000 years ago. The most

common domesticated animals today are cattle, sheep,

and pigs. However, a wide range of animals including

deer, rabbits, ducks, turkeys, and even ostriches are

now reared for their meat, milk, or eggs.

HOW HAVE MODERN CROPS BEEN DEVELOPED?

Today’s crops are descended from wild plants that

produced seeds or fruits that could be eaten. Early

cereal crops had small grains and therefore produced

low yields. However, new scientific methods can

generate disease-resistant plants or crops with

specific characteristics.

4 MECHANIZED FARMING

Modern combine harvesters

perform two jobs – harvesting

cereal crops and threshing the

grain to separate the husks

containing the seeds from the

stems. Farmers use different

machines to plough, sow,

reap, and to spray fields with

fertilizers and chemicals to

control weeds and pests.

CATTLE RANCHING 3

The world’s largest herds of beef

cattle are found in North and

South America, where there are

plenty of wide, open grasslands

for the cattle to graze. On these

South American grasslands,

cowboys called gauchos still

round up cattle on horseback.

Farming

RICE FARMING 3

Rice is the main food for over half

the world’s population. It is grown

in flooded fields called paddies in

countries such as Thailand, China,

Japan, and Indonesia.

Paddy fields are flooded for

most of the growing season

because rice, a swamp plant,

grows with its roots in water

Terraces are cut into

hillsides so farmers can

cultivate more land

farming