Hickory Tussock Moth Caterpillar

The Hickory Tussock Moth Caterpillar is a venomous caterpillar that has recently been spotted in Eastern Ontario. The caterpillar is white and fluffy and has black chain-like markings on its back. It also has long black hairs that stick out from areas near the front and back of the caterpillar. It grows to a length of about 4.5 centimeters.

Why should I be concerned about Hickory Tussock Moth Caterpillars?

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?

Wash the affected area with soap and water as soon as possible. In the case of itching or swelling, apply calamine lotion and/or ice packs to the affected areas. Individuals who experience more generalized allergic reactions should seek medical advice from a healthcare professional.

Where is the Hickory Tussock Moth caterpillar found?

The Hickory Tussock Moth Caterpillar is present in Southern Ontario. It feeds on the leaves of hickory, walnut, ash, elm and oak trees in preparation for overwintering in its cocoon.


  • 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. (5th ed.). Boca Raton: CRC Press, Taylor & Francis Group.

Developed by the Middlesex-London Health Unit and adapted with permission.