The venom 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 an allergic reaction which could include nausea.
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/or ice packs to affected areas. Individuals who experience more generalized allergic reactions should seek medical advice from their family physician.
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. The caterpillars grow to a length of about 4.5 centimeters.
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