Descurainia pinnata
 Descurainia pinnata is a species of flowering plant in the mustard family known by the common name western tansymustard. It is native to North America where it is widespread and found in varied habitats. It is especially successful in deserts. It is a hardy plant which easily becomes weedy and can spring up in disturbed barren sites with bad soil. This is a hairy heavily branched mustardlike annual which is quite variable in appearance.