Rhinanthus

(rattle), a genus of hemiparasitic plants of the family Scrophulariaceae. The plants are annual herbs with green, opposite, and usually serrate leaves. The flowers are mostly yellow and in spicate racemes; the corolla is two-lipped. The fruit, a laterally compressed capsule, has numerous winged (sometimes wingless) discoid seeds that rattle softly when the plant is shaken.

The approximately 50 species are found in the temperate and, to some degree, frigid zones of the northern hemisphere. The USSR has about 25 species, which grow mainly on wet meadows. R. vernalis (formerly R. major) and R. minor grow predominantly in forest and forest-steppe zones in wet meadows, along forest edges and the shores of bodies of water, and sometimes in fields. Both species, as well as many other species of Rhinanthus, parasitize the roots of meadow grasses and lower the yield and quality of hay. The plants are poisonous, since they contain the alkaloid rhinanthin. R. apterus, which is found predominantly in the forest zone of the European part of Western Siberia, is a weed of plantings of winter grains, mainly rye and wheat.