Preclearance - Inspection before shipment to the U.S.
Exclusion - Inspection and treatment before entry
Detection - Early detection of infestations
Containment - Established rules and procedures to stop the spread
Eradication - Means to eradicate infestations
The effectiveness of the regulations is challenged by many, including the industries that depend on the importation of nonindigenous species and the personnel that must enforce the regulations (Westbrooks 1993).
Frank and McCoy (1993:page 38) commented:
It is interesting to note that acting under the Plant Pest Act of 1912 and Plant Quarantine Act of 1957, U.S. Department of Agriculture agricultural inspectors have for decades tried to exclude phytophagous insects (plant pests) from entry into the USA, yet the U.S. Department of Agriculture has encouraged, and itself has taken part in, importation of exotic plants as ornamentals. This incongruity is explicable in terms of trade: sales of exotic terrestrial plants (by the nursery trade), exotic aquatic plants (by the aquarium trade), and exotic animals, especially vertebrates, but also mollusks and arthropods (by the pet trade) provide a profit to importers. Our laws make it acceptable to import worthless (i.e., unsalable) potential pests. We are not aware of anything in the laws that requires importers to pay for the control of imported organisms that have become pests, nor even to pay the cost of research toward finding means of control of such pests, although it strikes us as fair that they should do so.
Campbell (1993) summarized the legislation for the control of the introductions of exotic species into the United States and the major issues in the control of introductions.
A complete analysis of the Florida regulations about the importation and movement of arthropods was made by Denmark and Porter (1973). They emphasized that the applications to import insects, millipedes, mites, scorpions, spiders, ticks, snails, and protozoan malaria parasites were received and evaluated by a committee of state and federal agencies.


