Common name: Tansy, Common Tansy, Bitter Buttons, Cow Bitter, Mugwort, or Golden Buttons. Scientific name: Tanacetum vulgare. Family: Asteraceae. Genus: Tanacetum. Species: vulgare. Height: 50-150cm. Flowering time: Mid-to-late summer. Flower color: yellow.

Common tansy (Tanacetum vulgare) is a perennial, herbaceous flowering plant of the aster family. The flowers are yellow, roundish, flat-topped, button-like, have no petals. The leaves are alternate, 10–15 cm long and are pinnately lobed, no stalk. Tansy has a stout, erect stem, usually smooth, and branching near the top.