Also known as sisymbre Sophia and sagess-des-chirugiens, flixweed is a winter annual with a single branched stem from 30-100 cm tall. The branching is most common on the upper portion of the stem, but may also occur from near the base. The numerous leaves are mainly found on the stem and are 2-3 times pinnately compound. The segments are very narrow or linear, not measuring more than 1 mm in diameter. The leaves measure from 2-10 cm long and are short petiolate. A basal rosette of leaves is produced during the initial months of growth but often disappears by the time flowering occurs. The complex branching of the compound leaves of this species help distinguish it from other species of Descurainia.
The inflorescence is an elongate raceme which often accounts for up to one-half of the height of the plant. The slender pedicels measure 8-14 mm long and are strongly ascending. The 4 greenish sepals measure 2-1.5 mm long. The yellowish petals are spatulate and typically shorter than the sepals. The 6 stamens are well exserted from the flower. The siliques are linear in shape, measuring 2-3 cm long and 1-1.5 mm in diameter with slight constrictions of the pod between seeds. A prolific seed producer, this species readily spreads via seeds during the early to late summer. As a weed, it is a plant of concern because it robs crops of both moisture and nutrients. It has been reported to reduce crop yields of winter wheat and fall rye.
Flixweed may be found along roadsides, fields, waste places and other disturbed areas.
A native to Europe, flixweed may now be commonly found across much of the United States, from Alaska south to California and east to the Atlantic Ocean.
- -Flixweed observed around the lookout out buildings atop Bald Butte, about 8-10 miles north of Gearhart Mountain, Fremont-Winema National Forest......June 19, 2020.
A close-up of the distinctive bi- or tripinnate leaf of flixweed as seen along the John Day River adjacent to the fairgrounds in John Day, Oregon.......June 3, 2011.