The Sycamore Tussock Moth lives on and eats off of its namesake tree, sometimes to the point of destroying them.
Sycamore Tussock Moths can be found on sycamore trees and London plane trees. They are pale brown with alternating bands of tan and brown across the forewings. The hairy thorax has lines of white, blue and yellow hairs running down the center. This species looks identical to the Banded Tussock Moth of the same genus and only an anatomical inspection can really differentiate the two. Because it is impossible to check this via a photograph, on this website, the photos attributed to this moth are also placed on the Banded Tussock Moth.
Observers are more likely to find the caterpillars on the host trees, or possibly dangling from them by a fine strand, almost dancing their way to the ground. Sycamore Tussock Moth caterpillars grow to be about 25-35mm long. They are covered in white hairs and have orange heads. Four orange tufts (pencils) of long bristles extend upward behind the head. Four more white tufts (pencils) of long bristles are next to them. Two white pencils of long hairs extend out by the rear end. Though they are not reported to sting, this caterpillar has caused irritation on human skin, so handling them is not advised. Use a stick or paper to remove them from areas where they are not wanted. There are two to three generations each year.
Females lay fertilized eggs on the tree's bark or branches. The emerging caterpillars proceed to eat away at the leaves and soft plant tissue. In large numbers, annual substantial damage to the tree can kill it over time. After 30-40 days, the caterpillars form cocoons and will emerge as adults about two weeks later. An exception to that timeline is the generation of caterpillars pupating before winter comes. These caterpillars remain in their cocoons all season long, protecting them from the elements. They emerge as flying adults the next spring and will parent the first generation of that year.
Scientific Name: Halysidota harrisii
Butterfly or Moth
Size (Adult; Length): 25mm to 50mm (0.98in to 1.95in)
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Butterfly and Moth Anatomy
Antennae: Butterflies and Moths have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and proboscis.
Thorax: Home to the three pairs of legs as well as vital internal organs.
Abdomen: Contains vital internal organs such as the heart(s) and reproduction facilities.
Forewing: The upper, forward wing pair used for flying.
Hindwing: The lower, rearward wing pair used for flying.
NOTE: Butterflies and Moths are part of the Lepidopteran order as they share many similarities.