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(Achillea ptarmica, or Ptarmica vulgaris), a perennial herbaceous plant of the family Compositae. The stems are solitary and range from 20 to 125 cm in height. The biserrate and sessile leaves are entire, linear, or linear-lanceolate; they measure 1–8.5 cm in length and 1–6 mm in diameter. The hemispherical heads are about 20 mm wide and in a common corymbose inflorescence. The six to ten white marginal flowers are pistillate and ligulate; there are three curved denticles on the top. The off-white middle flowers are bisexual and tubular. Sneezewort grows in meadows, along bodies of water, and amid shrubbery in Europe, Asia Minor, and the European USSR. It occurs as an alien species in Western Siberia. The powdered dry herb causes sneezing. Varieties with double heads (with a predominance of ligulate flowers) are raised as ornamentals.