Helminthotheca echioides, known as bristly oxtongue, is a stiff annual or biennial herb native to Europe and North Africa. It was traditionally used as an antihelminthic treatment.
It can grow up to 90 cm (35 in) tall, with a thick, furrowed stem and spreading branches. The leaves are 10–20 cm (4–8 in) long, oblanceolate with a short petiole. The leaves, branches and stem are all covered in thick bristles. The inflorescences are 2–3.5 cm (0.8–1.4 in) wide and subtended by between 3 and 5 large ovate-cordate involucral bracts. These large bracts are the defining feature of the genus Helminthotheca.
It has been introduced to North America, where it can now be found from Nova Scotia to British Columbia and California.