For good reasons, cockroaches have the reputation for being the most hated of all pests in the US. Appearing unexpectedly in homes and businesses, this disease-carrying bug is considered by many to be the ultimate pest insect. Not only can they eat just about anything but also survive for weeks with no food. Roaches can even remain mobile for a few hours after being decapitated.
There are 69 species of roaches in the US. That number is increasing with new invaders arriving every few years. Until they appear as unwelcome visitors in the home, most people have little contact with roaches, as the majority live in the wild.
Although cockroaches can survive in a less than ideal environment, most species have a preference for a particular climate or habitat. For example, the American and the Smoky Brown roach are most likely to be encountered in the warmer southern states. But cockroaches can be found in all states, even becoming a growing nuisance in Alaska.
Roaches are fast-moving insects, easily recognized by their flat bodies and long antennae. Not all species have wings and those that do often prefer to run rather than fly when disturbed.
Of the reported pest infestations 95% are caused by only five of the 69 US species. Other species may occasionally appear in homes but these rarely cause trouble.
The pest species fall into two categories, large or small. Each category may be controlled in a different way, due to their habits.
American roaches are not the most common pest but can grow up to 3 inches in length. Other large species are the Oriental and the Smoky Brown cockroach, which grow to 1.25 and 1.5 inches in length respectively.
The German cockroach is the most prevalent roach pest in the US and at around half an inch in length is classed as a small roach. They make up for their size with the speed at which they reproduce and quickly become a serious problem if not dealt with swiftly.
Another common pest species in the small roach category is the Brown Banded cockroach.
Like all insects, cockroaches reach maturity through various stages of metamorphosis: egg, nymph, and adult.
Eggs are protected inside a small hard capsule, called an ootheca. Each ootheca may contain between 10 and 50 eggs depending on the species and is normally laid out of sight. Nymphs hatch from the eggs and force their way out of the ootheca.
Nymphs of most species will undergo six skin changes before they become adults. They look like small versions of adult roaches, except in species with wings, which only become visible after the last molt.
German roaches differ from other pest roaches as the females retain the oothecae in their body until the eggs are close to hatching.