Swallowtails and Monarchs are starting to become common sights flying through the yard. Here an Eastern Tiger Swallowtail, Papilio glaucus, stopped to sip at the Ironweed, Vernonia sp.
I rarely see anything on the Ironweed, especially compared to other plants flowering at this time like Mountain Mint, Button Bush, and Anise Hyssop. They're just starting to open up though so I'll give it a few more weeks before rendering my final judgment on them. When I do see pollinators on Ironweed it tends to be butterflies so that's a plus.