The Common Buttonbush, Cephalanthus occidentalis, is poisonous to humans but it absolutely ushers in the butterflies to sip from it's pin cushion flower head. This plant of the Madder family grows across the United States but in my encounters it's always near some swampy land or river. Recently while in Riverbend Park and Blue Spring State Park, I saw Common Buttonbushes growing on the riverbanks. And both of the plant had butterflies, though of different species.
The butterfly I saw at Riverbend was a Palamedes Swallowtail, Papilio palamedes. This large swallow tail is one of the largest butterflies in the United States. The only swallowtail that rivals it in size it's the Eastern Tiger Swallowtail, Papilio gaucus. Below is a few shots of the Eastern Tiger Swallowtail seen form the headwaters of Blue Springs.
Swallowtails are relatives to the Birdwings, the largest butterflies in the world. Not all swallowtails have "tails" but most of them do have them. Both of these large butterflies were easy to see and I followed them way into the distance. Summer may be slow when it comes to birding but at least I have the butterflies.