[7] Trillium stamineum is a perennial herbaceous plant that spreads by means of underground rhizomes.

The plant has three sessile bracts (leaves) arranged in a whorl about a pubescent scape (stem) that rises directly from the rhizome 15 to 30 cm (5.9 to 11.8 in) high.

Unlike other sessile-flowered trilliums, the petals spread horizontally (instead of vertically) exposing stiffly erect stamens 16 to 24 mm (0.6 to 0.9 in) long.

[10] The former is distinguished by its pubescent stem, unusual petals, long erect stamens, and very short filaments.

Trillium stamineum was named and described by the American botanist Thomas Grant Harbison in 1901.