Sisymbrium linifolium, synonyms including Schoenocrambe linifolia, is a species of flowering plant in the mustard family,[1] known by the common names flaxleaf plainsmustard, skeleton mustard, and Salmon River plains-mustard.

It is native to western North America, where it can be found from British Columbia east of the Cascade Range to Saskatchewan in Canada and south to Arizona and New Mexico in the United States.

[3] This perennial plant produces erect stems up to half a meter tall from a caudex.

[3] This plant occurs in many types of habitat, including salt-desert shrub, sagebrush, pinyon-juniper woodland, mountain shrub, and habitat dominated by Ponderosa pine (Pinus ponderosa), and trembling aspen (Populus tremuloides).

It is the most common forb in a number of regions, including a pinyon-sagebrush transition in northeastern Utah and the grasslands of the Snake River Plain.