Asclepias tuberosa

R. W. Smith
B. S. Walters
B. S. Walters
M. Demmon
ex W. H. Wagner slide collection flower, top view
Ann Arbor Natural Area Preservation fruits opening
Ann Arbor Natural Area Preservation
B. S. Walters with A. syriaca
B. S. Walters inflorescence
A. A. Reznicek fruits and seeds
C. Peirce
J. Kelly seed pod