Field photograph of Sullivant’s Milkweed (Asclepias sullivantii). Monarch butterfly visiting Sullivant’s Milkweed flowers among pink-veined leaves and prairie grasses. Photograph by Brian Woolman for Where’s Wildlife. Original image: Monarch-Butterfly-on-Sullivants-Milkweed-Asclepias-sullivantii-DSCN23599.jpg.