![]() ![]() Bed bug ![]() ![]() |
The history of pest control probably began with the first human who ever swatted a mosquito or picked off a louse. From the fossil record, we know that all major taxa of biting flies and external parasites already existed by the time Homo sapiens first appeared on earth. Phthirus and Pediculus, the two genera of lice that feed on humans, have a host range that is limited to primates (apes and monkeys). And we suspect that human fleas (Pulex irritans) and bed bugs (Cimex lectularius) adopted cave-dwellers as hosts because these insects are most closely related to other species that live on bats. But since our primitive ancestors were hunters and gatherers, they probably found that insects were more useful as food than they were troublesome as pests. (Even today, people in some primitive cultures eat the lice they pick from one another's hair). It was probably not until the dawn of organized agriculture, when insects attacked the plants we grew for food, that we first recognized them as a potential threat to our own survival.
Pest control tactics were mentioned occasionally in writings of the ancient Chinese, Sumerian, and Egyptian scholars. Many of these tactics were embedded in religion or superstition, but a few had real scientific merit. Predatory ants, for example, were used in China as early as 1200 B.C. to protect citrus groves from caterpillars and wood boring beetles. Ropes or bamboo sticks tied between adjacent branches helped the ants move easily from place to place.
There was very little progress in pest control during the dark ages. Ignorance and superstition abounded. For what it was worth, St. Bernhard excommunicated the flies of his parish in 1121. In a book entitled "Natural History", Ferrante Imperato (1599) gave a prescription for eliminating flies from a dwelling: "... draw the image of a fly ... on a copper plate during the second half of the constellation of Pisces ... then bury it in the center of your house (during) the first half of the constellation of Taurus." |
![]() ![]() Victorian flea trap (circa 1840) |
![]() Since the late 1800's, entomologists and chemists have made outstanding progress in the technology of pest control. Today's arsenal of weapons is large and diverse, encompassing legal, cultural, physical, genetic, and biological tactics, in addition to the well-known chemical pesticides. In general, all of these tactics work in at least one of the following ways:
Most of the control tactics that are commonly used today can be grouped into two broad categories: natural controls and artificial controls. By definition, a natural control may be any environmental factor that keeps a pest population below its economic injury level. Examples might include geographic barriers, cold temperatures, or natural enemies that keep population growth in check. Artificial controls, on the other hand, employ products or processes of human origin to modify a pest's distribution, behavior or physiology. Fly swatters and insecticides are two obvious examples. But as is often true in biology, there are some control strategies that seem to straddle the line, exhibiting characteristics of both groups or not fitting neatly into either category. In fact, some of our most effective tactics are natural controls that we can improve, enhance, accelerate, or augment by appropriate human intervention.
|
Last Updated: 4 November 2003 Return to ENT 425 Homepage |
John R. Meyer
Department of Entomology NC State University |