(गाजरघास) Parthenium hysterophorus
Common Name : Congress grass Family: Asteraceae Habit: A short-lived annual herb with an extensive root system and an erect shoot; up to 2 m high. Stem: Erect main stem, upper half of the main stem becomes highly-branched at flowering; stems appear to be striped due to longitudinal grooves or ribs and they become woody with age. Leaves: Pale green, deeply lobed and covered with fine soft hairs. Flowers: Creamy-white flowers occur at the tips of the stems. Clusters of male and female florets are grouped as five-lobed flowers on the terminal branches of the flower stem and measure 4–6 mm in diameter. Fruits: Achene small (1–2 mm across), flattened, triangular and dark brown–black with two thin, white, spoon-shaped appendages.