The Colorado potato beetle (Leptinotarsa decemlineata), commonly called the "potato bug," is native to North America. It once fed solely on the buffalo burr plant, but when European settlers introduced potatoes to this country, the insect quickly found a new favorite food. In 1859 the beetles began to attack potato crops outside Omaha, Nebraska, and the surrounding area, according to the University of Florida. By 1874, the potato bug had spread from coast to coast, consuming potato crops nationwide.
Potato bugs defoliate and quickly kill a potato plant. In addition to potatoes, they feed on tomatoes, cabbage, peppers and eggplants. The bugs also feed on weeds such as jimson, horse nettle and belladonna.
During winter, potato bugs hibernate by burrowing into the soil. Each spring and early summer, the beetles emerge from the soil to feed on foliage when the danger of hard frost has passed. The potato bugs are voracious eaters that will enter the soil at the base of the plants to feed on the new foliage before it sprouts from the ground.
Female potato bugs lay their eggs on the underside of leaves. In four to five weeks, a female potato bug will lay close to 500 eggs. Within four to nine days, the eggs begin to hatch and the larvae feed on the foliage of the plant. During the larval stage, the feeding is non-stop and quite severe.
Pupal To Beetle
After three weeks of heavy feeding, the larvae enter the ground and become pupals. The full-grown beetles emerge from the pupal stage. The entire egg-to-beetle process lasts only 21 days. Once potato bugs are adult beetles, the females feed for a few days, then begin laying eggs and the the cycle starts all over. Potato bugs can go through three cycles in one summer.
The potato bug has gained a very high resistance to most pesticides. Numerous pesticides are needed to control a heavy infestation. The pesticides offer the most success when applied at rotating intervals. Applications of foliar sprays prove the most effective when applied after the eggs have hatched. Biopesticides hold a great deal of promise for control. The biopesticides contain a naturally occurring bacterial disease, Bacillus thuringiensis, which successfully kills the potato bugs.