The flowers are fragrant and attractive to many insects. A beautiful metallic-iridescent leaf-beetle, Chrysochus auratus Fabr., is known as the “dogbane beetle” because of its regular association with Apocynum (its larvae feed on the roots).
1. Corolla (5–) 5.5–8 (–9) mm long when mature, with spreading to recurved lobes, pink to rosy (at least in lines within) when fresh; leaves ovate to broadly elliptic, widely spreading or drooping.
1. Corolla 2.5–4 (–4.5) mm long, with erect lobes when mature, white to greenish when fresh; leaves oblong to broadly lanceolate, ± strongly ascending.
All species found in Apocynum
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 12, 2018. https://michiganflora.net/genus.aspx?id=Apocynum.