Flixweed (Descurainia sophia)

Flixweed description

Flixweed is an annual, winter annual, or a biennial weed of crops. The grayish-green plant grows up to 1 m high.

Propagation

Annual, winter annual, or biennial.

Similar species

Sometimes mistakenly called tansy mustard, although true tansy mustards are a different species.

Flixweed can be differentiated from the tansy mustards by its longer seed pods. The pods of flixweed are 1/2 to 1-1/4 inches long, the pods of the tansy mustards are much shorter, 1/4 to slightly less than 3/4 inch. Flixweed is usually more common than the tansy mustards.

Distribution

Flixweed can be found throughout the Prairie provinces, and in scattered localities throughout Ontario

Identifying Flixweed

Seedling

Cotyledons small, elliptic with rounded tips. First two true leaves opposite, 3 lobed. Remaining leaves are alternate, finely divided and grey-green, with fine hairs.

Mature plant

Stems are erect, much branched, 8 to 40 inches at maturity. Stems appear grey-green because of star-like hairs.

Leaves are alternate, 1 to 4 inches long, finely divided into narrow segments, covered with star-like hairs usually giving the leaves a grey color. Basal rosette of leaves usually withers by flowering time.

Root structure description

Taproot.

Flowers

Pale yellow, very small, in dense clusters at ends of branches. Flowers throughout the summer. Flower stalks elongate to make up about half the plant height, as seed matures. Seed pods about 3/4 inch long, on stalks 1/4 inch long. Pods slightly curved and very narrow. Orange seeds in one row of each side of the pod.