Hairy balls at Olbrich Botanical Gardens. Really, that's what this plant is called.
Hairy Balls photographed at dusk in Olbrich Gardens. Really. That's what this plant is called -- unless you want to go the Latin route, and then its name is Gomphocarpus physocarpus. The faint of heart may choose to call it the Swan Plant, Balloon Plant, or Giant Swan Milkweed instead.