Schiedea menziesii is a sprawling perennial herb that becomes woody towards the base. It typically grows 30 to 100 cm long and is multi-stemmed from the base, forming clumps. The primary stems are many-branched, weakly ascending to sprawling, and exhibit a green or purple tinge. The lower parts of the stems are glabrous, while the upper stems and inflorescence are usually densely puberulent. A fibrous root system supports the plant. The leaves are simple and opposite, with linear to linear-lanceolate or linear-elliptic falcate blades measuring 2 to 9 cm in length and 0.15 to 1 cm in width. The leaf apex is attenuate and often recurved, while the base gradually tapers. The leaf surfaces are glabrous except along the midvein, margin, and towards the base, where they are puberulent. The blades are thin, membranous, and slightly revolute at the margins. There are one or three principal veins, with the midvein being eccentric. The petioles are weakly to conspicuously connate around the stem. Stipules are absent. The flowers form in a terminal inflorescence with 8 to 100 flowers, measuring 2 to 8 (sometimes up to 10) cm long. The inflorescence is laterally contracted, with branches and pedicels ascending to somewhat appressed and moderately puberulent. The bracts are green, linear to subulate. The pedicels are 3 to 9 mm long, slender, and inconspicuously flattened. The flowers are bisexual (perfect), with sepals measuring 4 to 5 mm long, narrowly lanceolate, and usually undulate, green, opaque, and strongly reflexed. The corolla (petals) is absent. There are 10 stamens with subequal filaments and yellow anthers. The superior ovary is 1-celled, with free-central ovule placentation and 3 to 4 styles. The fruit is an ovoid capsule measuring 3 to 4.5 mm long, with seeds approximately 0.8 mm long, orbicular-reniform, compressed. The perisperm (nutritive tissue surrounding the embryo) is starchy, with no true endosperm. It is uncommon and typically found on ledges and cliffs in shrublands between 30-670 meters.