Rocky Mountain wood tick

arachnid

Also known as: Dermacentor andersoni

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Last updated

July 15, 2026

Quick Summary

The Rocky Mountain wood tick (Dermacentor andersoni) is an arachnid found in western North America, primarily in areas ranging from 4,000 to 10,000 feet in elevation. These ticks are known vectors for serious diseases, including Rocky Mountain spotted fever and Colorado tick fever.123

Ticks are obligate, blood-feeding parasites and are significant carriers of diseases to animals and humans. The Rocky Mountain wood tick is active in late spring and summer. Prevention of tick bites is crucial, involving avoiding tick-prone areas and using protective clothing and repellents.42

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Colorado tick fever
…Rocky Mountain wood tick (Dermacentor andersoni).. Colorado tick fever is relatively rare; between 2003 and 2022, just 223 cases were reported in the United States.
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…Rocky Mountain wood tick (Dermacentor andersoni).. Colorado tick fever is relatively rare; between 2003 and 2022, just 223 cases were reported in the United States.
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Rocky Mountain spotted fever
…the carrier species is the wood tick, Dermacentor andersoni, which is widely distributed in the adult form on large mammals, particularly cattle and sheep. In the eastern and southern United States, the common dog tick, Dermacentor variabilis, which attacks humans, also acts as a carrier. In the southwestern United States,…
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…the carrier species is the wood tick, Dermacentor andersoni, which is widely distributed in the adult form on large mammals, particularly cattle and sheep. In the eastern and southern United States, the common dog tick, Dermacentor variabilis, which attacks humans, also acts as a carrier. In the southwestern United States,…
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tick
Diseases
In recent years
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In recent years
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