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Issue: Plant Pesticides Impact less on Non-target Organisms Genetically modified plants that produce their own plant pesticides include Bt cotton, Bt corn, Bt sweet corn, and Bt potatoes. These plant pesticides are very selective.  For example, the type of Bt in Bt corn only controls the caterpillars of some moths and butterflies. The type of Bt in Bt potatoes controls Colorado potato beetles. In addition, the Bt is inside the plant, so only insects that feed on the plant or plant parts are exposed to the plant pesticide. An exception to this is with the pollen from Bt corn which is wind blown. Some Bt-corn pollen also contains the Bt toxin. It has been shown in the laboratory to reduce the survival of monarch caterpillars that have been feed on milkweed plants that were dusted with this pollen.  However field studies indicate negligible impact of corn pollen containing Bt on monarch butterfly larvae.   But it is important to keep in mind that these genetically modified crops that produce their own plant pesticides require fewer pesticide sprays. Most of the commonly used insecticide used on these crops are referred to as broad spectrum insecticides. They are generally as toxic to non-target organisms as they are to the target pest. Plants that produce their own plant pesticides are more selective in terms of controlling pests without damaging non-target organisms. Their impact on non-target organisms is further reduced because they require fewer broad spectrum pesticide sprays. Impacts of Bt cotton and corn on non-target arthropods