Organic farming is a form of agriculture which excludes the use of synthetic fertilizers and pesticides, plant growth regulators, livestock feed additives, and genetically modified organisms. As far as possible, organic farmers rely on crop rotation, green manure, crop residue, compost and mechanical cultivation to maintain soil productivity and control pests.Organic agricultural methods are internationally regulated and legally enforced by many nations, based in large part on the standards set by the International Federation of Organic Agriculture Movements, an international umbrella organization for organic organizations. Approximately 310,000 square kilometres (75 million acres) worldwide are now grown organically.The overarching goal of organic farming is defined as follows:"The role of organic agriculture, whether in farming, processing, distribution, or consumption, is to sustain and enhance the health of ecosystems and organisms from the smallest in the soil to human beings."—International Federation of Organic Agriculture Movement (IFOAM) - The Principles of Organic Agriculture - Principle of health