Three-toothed horkelia (Horkelia tridentata) is a native perennial found in Oregon, California and Nevada. It grows between 2,000 and 6,500 feet in ponderosa pine and red fir forests.
The genus name, Horkelia, honors Johann Horkel (1769 – 1846), a physician and plant physiologist. The three teeth at the apex of each leaflet give the plant its species name. In Latin, tridentata, means three-toothed.
Three-toothed horkelia arises from a thick, woody rootstock. The entire plant is pilose, covered in soft hairs. The green or reddish stems are decumbent or upright.
The leaves of three-toothed horkelia are mostly basal, with only a few occurring on the stems. The leaves are pinnately compound with two to seven opposite pairs of leaflets.
The inflorescence is a compact cyme. Cymes are branched clusters of flowers with the central flowers maturing first. There are five minute bracts surrounding five hairy, pointed sepals. The five narrow, white petals look as though they are emerging from the cuplike base formed by the sepals. The ten stamens are flattened.
In May these three-toothed horkelia were growing along Shasta National Forest Road 40N04 near Timbered Crater (Shasta County CA).