Organic farming is an alternative agricultural system which originated
early in the 20th century in reaction to rapidly changing farming practices.
Organic agriculture continues to be developed by various organic agriculture
organizations today. It relies on 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. Biological pest control, mixed
cropping and the fostering of insect predators are encouraged