Herbicides, commonly known as weed killers, are pesticides used to kill unwanted plants. Some are selective and interfere with growth of specific plants, while others are non-selective and kill all treated plant material. They are commonly used in agriculture and forestry; on lawns, gardens and golf courses; and to control weeds in industrial areas.
Many modern chemical herbicides for agriculture are specifically formulated to decompose quickly after application. This advancement is beneficial in avoiding water contamination and allows crops that may be affected by the herbicide to be grown in future seasons.
All commercially sold organic and nonorganic herbicides in the United States must be extensively tested prior to gaining labeling and sale approval from the Environmental Protection Agency.
The EPA uses the latest scientific research to set maximum residue levels, which are hundreds of times higher than toxic levels, for crops. The USDA is responsible for testing crops each year to ensure they do not go above the tolerances and the FDA has regulatory authority to enforce penalties for non-compliance.
Producers are legally and ethically required to use herbicides according to the EPA approved label instructions. They are highly diluted with water and applied precisely where they are needed to avoid overspray. In most agricultural applications, this equates to applying less than one quart of chemical over a plot of land the size of a fooball field.