Banded Tussock or Sycamore Tussock. Adult moths of these two species can only be identified with dissection. However, the caterpillars look quite different and can easily be identified. (See my caterpillar pages for photos.) Judging by the number of caterpillars I see, Banded Tussocks are apparently the more common of the two species, but we do have Sycamore Tussocks in this area as well. I find many of the adults at my lights from May through September (mostly in the summer months). 

Hickory Tussock. A very common species that flies from late April through early June. It is known for its "stinging" white caterpillar that can cause a painful rash if handled.