Western bitterweed

Hymenoxys odorata DC.

Asteraceae (Sunflower Family)


Western bitterweed is an erect, annual, composite plant in the Sunflower family. It reaches 3 inches to 2 feet tall. The stems are purplish near the base. This plant has a bitter taste and a distinct odor.

The leaves usually are woolly underneath and are located alternately along the stems.

Bright yellow flowers bloom from April through June and occasionally in the fall. With adequate rainfall, it is common to see pastures turn yellow with this plant in the spring.

Western bitterweed is highly toxic to sheep, especially during drought.


Bitterweed is common in arid areas of the southern Great Plains from southwestern Kansas and central Texas to southern California and into Mexico. It is most common where soil disturbance or overgrazing has occurred. The populations can vary considerably from year to year.