Pest: see Budapest, Hungary.

Integrated Pest Management (IPM), planned program that coordinates economically and environmentally acceptable methods of pest control with the judicious and minimal use of toxic pesticides. IPM programs are based on a careful assessment of local conditions, including such factors as climate, crop characteristics, the biology of the pest species, agricultural practices, soil quality, and government regulations. The tactics employed range from changes in agricultural methods, such as better tillage to prevent soil erosion and interplanting of different crop varieties; natural biological weapons, such as the introduction of beneficial insects that eat the harmful species; and mechanical tools, such as vacuums that pull the insects off of the crops. Toxic pesticides are used only when all other methods have failed. See also organic farming; pesticides.

Any organism, usually an animal, judged as a threat to humans. Most pests either compete with humans for natural resources or transmit disease to humans, their crops, or their livestock. Invertebrate pests include some protozoans, flatworms, nematodes, mollusks, arachnids, and especially insects. Mammals and birds can also be pests. Human activities, such as monocultural farming practices, use of broad-spectrum pesticides, and introduction of exotic species, often result in the proliferation of pest species. Certain fungi, bacteria, and viruses are also considered pests. Plant pests are usually called weeds.

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