1. Leaflets 3, with 3–6 large teeth per side; flowers in small (ca. 1 cm) dense inflorescences on short lateral shoots (± coalescing in fruit), opening before the leaves.
1. Leaflets 7–23, entire or with 6–15 teeth per side; flowers in large inflorescences, opening after the leaves.
2. Rachis ± winged, especially between distal leaflets; leaflets usually entire, occasionally with scattered teeth near the apex, rarely more toothed.
2. Rachis not winged; leaflets toothed to the base.
3. Petioles and new branches glabrous or nearly so; hairs on fruit less than 0.5 mm long, mostly clavate to obovoid; leaflets glabrous beneath (or with a few hairs) [see text for intermediate plants].
3. Petioles and new branches with ± dense pubescence including many long (mostly 1–2 mm) straight hairs; hairs on fruit mostly 1–2 mm long, tapering to a sharp point (very short obovoid hairs may also be present); leaflets pubescent beneath, at least on veins.
All species found in Rhus
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. June 16, 2019. https://www.michiganflora.net/genus.aspx?id=Rhus.