Vernonia gigantea (Giant Ironweed)

Native to southeastern Canada and the central and eastern United States, this perennial herb belongs to the daisy family. It usually grows about 3 to 5 feet tall but can reach 12 feet. Stiff, upright stems carry toothed leaves and branching clusters of purple flower heads made entirely of tubular florets. Bees and butterflies visit the flowers, and the dry fruits have bristles that help them travel on the wind. Livestock generally avoid its bitter foliage. It grows in moist meadows, floodplains, and woodland margins, and its dead, hollow stems provide nesting sites for native bees. Photographed in Florida.