The leaves of Smodingium argutum are spirally arranged or alternate on the stems, growing on slender, long, hairy stalks of 5 cm to 8 cm.
The leaf shape is trifoliolate, the leaflet narrowly ovate with tapering base and tip; the terminal leaflet slightly larger than the lateral ones. Leaflet margins have pronounced toothing, but are entire near the base. There are hardly petiolules (leaflet stalks) present on leaflets. The leaflet dimensions are 7 cm to 13 cm by 2,5 cm to 4 cm.
The leaflet colour is dark green above and shiny, while paler below. The texture is leathery and hairless. Midribs and lateral veins are prominent on both surfaces.
Very small, cream flowers grow in large, branched, terminal sprays from midsummer through autumn. The fruit is a flattened achene, a small, dry one-seeded fruit that does not open to release the seed, enclosed in a red, papery wing (Coates Palgrave, 2002; Pooley, 1993).