Organic farming is a form of
agriculture that relies on techniques such as
crop rotation,
green manure,
compost, and
biological pest control. Depending on whose
definition is used, organic farming uses fertilizers and pesticides (which include
herbicides,
insecticides and
fungicides) if they are considered
natural (such as
bone meal from animals or
pyrethrin from flowers), but it excludes or strictly limits the use of various methods (including synthetic petrochemical
fertilizers and
pesticides;
plant growth regulators such as
hormones;
antibiotic use in livestock;
genetically modified organisms; human sewage
sludge; and
nanomaterials) in pursuit of goals including
sustainability,
openness,
independence,
health, and
safety.