Organic farming is a form of agriculture that relies on crop rotation, green manure, compost, biological pest control, and mechanical cultivation to maintain soil productivity and control pests, excluding or strictly limiting the use of synthetic fertilizers and synthetic pesticides, plant growth regulators, livestock feed additives, and genetically modified organisms. Since 1990, the market for organic products has grown at a rapid pace, to reach $46 billion in 2007. This demand has driven a similar increase in organically managed farmland. Approximately 32.2 million hectares worldwide are now farmed organically, representing approximately 0.8 percent of total world farmland. In addition, as of 2007 organic wild products are harvested on approximately 30 million hectares