Apocynum × floribundum, the intermediate dogbane, is a member of the family Apocynaceae. It is widespread across Canada, the United States, and northern Mexico.Kew World Checklist of Selected Plant FamiliesBiota of North America Program 2013 county distribution mapDouglas, G.W., Meidinger, D. & Penny, J.L. (2002). Rare Native Vascular Plants of British Columbia, ed. 2: 1-358. Province of British Columbia.Larson, J., Reif, B., Nelson, B.E. & Hartman, R.L. (2014). Floristic studies in North Central New Mexico, U.S.A. the Sange de Cristo mountains. Journal of the Botanical Research Institute of Texas 8: 271-303.
Intermediate dogbane is believed to be of hybrid origin because its characteristics are intermediate between A. cannabinum (dogbane) and A. androsaemifolium (spreading dogbane).
References
External links USDA Plants Profile for Apocynum × floribundum Wisplants.uwsp.edu: Apocynum × floribundum (hybrid Intermediate Dogbane) Mit.edu: photo of hybrid Intermediate Dogbane