Sycamore tussock moth

The Sycamore Tussock Moth caterpillar has been known to cause urticaria (hives) to those who touch its hairs. This defense mechanism protects the caterpillar from potential predators. If you find a Sycamore Tussock Moth crawling on you don't pick it up of swat at it. Use a folded piece of paper or stick to gently remove it. Acting aggressively toward the caterpillar increases the likelihood of exposure to those defensive hairs.