What Is a Wood Tick?

A wood tick is a parasitic arachnid belonging to the Ixodoidea taxonomic superfamily. These less-than-appealing little insects survive by latching onto a warm-blooded host and gorging themselves with the host’s blood until they swell to several times their original size. The wood tick is also a known transmitter of several diseases, such as Rocky Mountain spotted fever and Lyme disease. The insects share the same habitats with most tick species, waiting patiently on blades of grass or low shrubs for a suitable host to brush up against them and afford an opportunity to climb on board to feed.

Ticks are parasitic arachnids similar in physical features to spiders and mites. Part of the Ixodoidea superfamily, ticks make a living by gorging themselves on the blood of unwilling, and usually unknowing, warm-blooded hosts. As is the case with most parasitic creatures that rely on a diet of blood for survival, the tick will feed on animals, birds, and humans as the opportunity presents itself. This presents a very real risk of cross-transmission of diseases, such as Lyme, Rocky Mountain spotted fever, ehrlichiosis, and tularemia. Apart from the unpleasant, itchy bites, this danger of disease transmission should be the main reason for trying at all costs to avoid tick bites.

The wood tick is one of the Dermacentor genus of hard ticks. The name can be confusing at times as other tick types such as the American dog tick — Dermacentor variabilis — are also frequently referred to as wood ticks. The more accurate application of the name, however, is the Rocky Mountain wood tick, or Dermacentor andersoni. Both male and female wood ticks are approximately 3/16th of an inch (5.5 mm) long when unfed and can swell to 0.5 inches (13 mm) when gorged. Female wood ticks sport a large silver dot behind their heads, while the males have fine silver lines across their backs.

Both variabilis and andersoni subspecies are known carriers and transmitters of Rocky Mountain spotted fever among other diseases, with the American dog tick also being responsible for the spread of Lyme disease. The Rocky Mountain wood tick is known to carry Lyme, but its transferal potential of the disease is uncertain. It is this disease-spreading potential that makes tick bite prevention a crucial part of any outdoor activity. The use of insect repellents and the wearing of tight-cuffed clothing does help, although regular inspections of all exposed skin areas is usually the best first line of defense. Ticks can fairly quickly migrate from the legs and feet to the hair with the host being unaware.