The tansy (Tanacetum vulgare) is a perennial herbaceous plant of the Tanacetum genus in the Asteraceae family, native to temperate areas of Asia and Europe.
The Tanacetum genus includes around 160 species[1] of flowering plants. Common names include golden buttons, cow bitter, or bitter buttons. The specific epithet Vulgare is a Latin word that means “common“.
Tansy is a flowering plant with finely serrated compound leaves and yellow button-shaped flowers. It has a robust, somewhat reddish, upright stem, generally smooth, straight 50 to150 cm (20 to 59 inches) high, and branched near the tip.
The alternate leaves are 10 to 15 cm (3.9 to 5.9 inches) long and divided almost halfway into seven segments or lobes, giving the leaf a fern-like appearance.
In mid to late summer, the rounded, flattened, button-shaped yellow inflorescences are produced in terminal racemes.