Streptanthus barbatus bristly edges (no more than 3 centimeters long) and borne on short petioles. Leaves above these are oval to rounded and may clasp the stem. Flowers occur at intervals along the upper stem. Each has a spherical to urn-shaped calyx of keeled sepals under a centimeter long with curving petals barely emerging from the tip. The calyx of sepals is whitish, darkening purple in maturity. The petals are purple. The fruit is a long, flat, curving silique which may be 7 centimeters in length. Streptanthus barbatus Streptanthus barbatus is a species of flowering plant in the mustard family known by
Polygonum ramosissimum calyx. The calyx is around long and 5-parted with the outer three sepals longer than the inner sepals. The seeds are produced in fruits called achenes, which are egg-shaped, dark brown and around long. The achenes also have a smooth shiny surface. The late season achenes are larger, from 4 to 15 mm long. There are a number of forms and two subspecies, that vary in flower and foliage coloration. "Polygonum ramosissimum" has great morphological variability, which is notable on the same plant, between flowers and fruits produced early in the blooming season verses those produced late in the season,