hickory tussock caterpillar

What is a Hickory Tussock Moth caterpillar?

The caterpillar is white and fluffy and has black chain-like markings on its back. It also has long black hairs that protrude from areas near the front and rear of the caterpillar; these hairs are connected to poison glands which excrete venom on contact. It grows to a length of about 4.5 centimeters.

What happens after you touch a Hickory Tussock Moth caterpillar?

Touching these caterpillars can cause a rash similar to that caused by nettles or poison ivy. Symptoms can range from slight reddening of the skin to a burning sensation with swelling and pain. Some people may experience a headache, nausea or an allergic reaction.

What should I do if I have touched one of these caterpillars?

  • The Health Unit recommends that anyone who touches a Hickory Tussock Moth Caterpillar wash the affected area with soap and water as soon as possible.
  • In the case of itching or swelling, apply calamine lotion and ice packs to the affected areas.
  • Individuals who experience more generalized allergic reactions should seek medical advice from a doctor.

Where is the Hickory Tussock Moth caterpillar found?

The Hickory Tussock Moth Caterpillar is present in Southern Ontario from July to September, at which time it feeds on the leaves of hickory, walnut, ash, elm and oak trees in preparation for overwintering in its cocoon

Adapted with permission from the Middlesex-London Health Unit and the Oxford County Public Health. Photograph courtesy of Oxford County Public Health.


  • Wagner, D.L. (2005). Caterpillars of eastern North America: A guide to identification and natural history. New Jersey: Princeton University Press.
  • Goddard, J. (2007). Physician’s guide to arthropods of medical importance. (Fifth Edition). Boca Raton: CRC Press, Taylor and Francis Group.