The cultivation of a single crop on a piece of land to the exclusion of other crops. This generally requires large quantities of artificial fertilizers, herbicides, pesticides, nematocides, and other potentiall toxic measures to kill bugs and increase yield. Even with these chemical aids, monocultures are prone to disease outbreaks and pest infestations. Wes Jackson (New Roots for Agriculture): agriculture leads to the monoculture of annuals, nature to the polyculture of perennials. Monoculture invites pests, diseases, erosion.