Physocarpus opulifolius var. tomentellus (Seringe) B. Boivin
Physocarpus opulifolius var. tomentellus (Seringe) B. Boivin is a synonym sensu FNA Ed. Comm., 2014 of:
Physocarpus capitatus (Pursh) Kuntze, an accepted species name sensu FNA Ed. Comm., 2014.