Organic farming, also known as ecological farming or biological farming,
is an agricultural system that uses fertilizers of organic origin such
as compost manure, green manure, and bone meal and places emphasis on
techniques such as crop rotation and companion planting. It originated
early in the 20th century in reaction to rapidly changing farming
practices. Certified organic agriculture accounts for 70 million
hectares (170 million acres) globally, with over half of that total in
Australia. Organic farming continues to be developed by various
organizations today. Biological pest control, mixed cropping and the
fostering of insect predators are encouraged. Organic standards are
designed to allow the use of naturally-occurring substances while
prohibiting or strictly limiting synthetic substances.
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