Any of a wide range of chemical, physical, and biological methods used to reduce levels of insect pests, plant pathogens, and weed populations.
Pests annually destroy about one-third of all crops worldwide.
More than half the pesticides used in the United States are herbicides, and only a relatively small percentage of U.S. agricultural land areas are treated with pesticides. The amount of pesticide used on different crops also varies. For example, in the United States, most insecticides are applied to cotton and corn, most herbicides are applied to corn and soybeans, and most fungicides are applied to fruit and vegetable crops. Agricultural pesticides prevent billions of dollars in losses each year in the United States, but these benefits must be weighed against the costs to society of using pesticides, including human poisonings, fish kills, honey bee poisonings, and the contamination of livestock products. Nonchemical Controls Nonchemical control methods may be as simple as paper or plastic barriers placed around fruit trees to deter insects.