The Sycamore Tussock Moth (Halysidota harrisii) is a species of moth of the Erebidae family. It is found in South-Eastern Canada, the Eastern parts of the United States (but not Florida) and North-Eastern Mexico. The wingspan is about 50 mm. The moth flies from May to June and from July to August depending on the location. The larvae feed on the American Sycamore tree (Platanus occidentalis). Unfortunately, an overpopulation of the insect can be damaging to sycamore trees. The ideal way to manage the moth and caterpillar populations is to foster a healthy bird population.