In terms of shear bulk, more of this pesticide has been used worldwide than all of the other carbamates combined. This has led to its wide-spread household use as a lawn and garden insecticide. Like the other carbamates, Carbaryl antagonizes acetylcholine and competes for binding sites on the enzyme cholinesterase. In agriculture, carbaryl is used as a contact insecticide recommended for use against pests of fruit, vegetables, cotton, and many other crops. Equally important are the agricultural crop losses due to weed infestation.
Weeds deprive the crops of moisture and nutritive substances from the soil.
In some instances they even shade crops and hinder their growth. The use of herbicides in the control of weeds is now a standard practice in the United States, and it has been estimated that we would have 10 to 12 percent of our population working on farms, manually dissecting weeds from the crops, were it not for herbicides. This powerful defoliant is a member of the bipyridylium class of pesticides. The two most important herbicides in this group are paraquat and diquat, both of which are contact herbicides that damage plant tissues quickly, causing the plants to appear frostbitten because of cell membrane destruction. This rapid degeneration occurs within hours of application, making these novel herbicides also useful as preharvest desiccants for seed crops, cotton, soybeans, sugarcane, and sunflowers.