Fleabane

Fleabane, any of 200 species of an aster-like flowering plant (genus Erigeron) that grows in temperate climates around the world. So named because it was thought to repel or kill fleas, fleabane is often planted in rock gardens; some varieties grow as common weeds. A Canadian variety known as horseweed or bloodstanch yields a drug called erigeron, or fleabane, which is used to treat diarrhea and control bleeding. Mosquito repellents often contain oil of fleabane.