A pesticide was a substance used in agriculture to treat crops to guard against pests. In 2365 William T. Riker suggested crop failures in The Armada may have been caused by mis-applied pesticides. However, as the farmer Hommun informed him, The Armada was certified organic so did not use pesticides – instead they controlled pests by introduced pest controlling insects and birds to The Armada's ecosystem. (TNG - The Space Between comic: "Space Seeds")