Schiedea salicaria is a gynodioecious (bears only female flowers) shrub species, typically growing 30 to 80 cm tall but can reach up to 180 cm. The stems, often swollen at the nodes, are terete, 4-angled or -ridged, and display an erect or strongly ascending growth pattern with a few short lateral branches in the distal part. They are glabrous with 0.5 to 5 cm long internodes and colored green to greenish-purple. The leaves are simple and opposite. The blades are narrowly elliptic to elliptic, sometimes elliptic-oblanceolate or oblanceolate, measuring 3 to 5.5 cm in length and 0.6 to 1.5 cm in width. The leaf apex is acute to acuminate, and the base is attenuate to narrowly cuneate. The blades are thinly coriaceous, pale yellowish-green, often slightly glaucous and reflective. The margins are entire, slightly thickened, and weakly revolute. There is typically one principal vein, with the outer pair being inconspicuous when present. The petioles are very short, ranging from 0 to 0.3 cm in length. Stipules are absent. The inflorescence is terminal, bearing 13 to 117 flowers and measuring 4 to 23 cm long. It is usually laterally contracted and weakly congested, with hermaphroditic inflorescences slightly less congested and broader than the pistillate ones. The flowers can be bisexual (perfect) or pistillate. The calyx of hermaphroditic flowers has sepals 3.1 to 4.1 mm long, narrowly ovate, and the pistillate flowers’ sepals are 2.75 to 4.2 mm long, narrowly ovate. The corolla (petals) is absent. The stamens are 10 to 12 in hermaphroditic flowers, with dimorphic filaments, and pistillate flowers have 10 to 12 vestigial stamens. The superior ovary is 1-celled, with free-central ovule placentation, and styles ranging from 2 to 4. The fruit is an ovoid capsule, 4.5 to 5 mm long, with seeds measuring 0.9 to 1.0 mm long, orbicular-reniform. The perisperm (nutritive tissue surrounding the embryo) is starchy, with no true endosperm. It is commonly found on ridges and steep slopes, usually beyond the reach of grazing animals, in remnant dry shrublands between 180-670 meters.