Eupatorium compositifolium Walter - Yankee Weed

Eupatorium compositifolium plant

Family - Asteraceae


Eupatorium compositifolium stem




Eupatorium compositifolium inflorescenceA portion of a flowering branch.



Ray flowers:


Disk flowers:

Eupatorium compositifolium flower headFlower head close-up.

Flowering - June - November.

Habitat - Flatwoods, marshes, pastures, disturbed sites.

Origin - Native to North America.

Other information - This weedy species can be found in the southern half of Alabama and is probably more common than has been reported. The plant can be identified by its pubescent stems, divided leaves, and dense but minute flower heads. The plant is often viscid when young. The stems grow to +2m tall.
Another species, E. capillifolium (Lam.) Small is similar but has leaf divisions that are very thin. The two species can be found growing side-by-side in the field.
The species epithet compositifolium derives from the Latin "compositus" meaning "placed together, compound, orderly" and "foli" meaning "a leaf" referring to the divided leaves of the plant.
The genus name Eupatorium was given in honor of Mithridates VI of Pontus (132BC - 63BC), also called Eupator Dionysius. Mithridates VI was the son of Mithridates V of Pontus (called Euergetes). Mithridates VI had many brothers, whom he killed to clear his path to the throne, and a sister, whom he married.
Mithridates VI is believed to have had a tremendous memory. It is said he spoke 25 different languages. It is also believed that Mithridates sought to strengthen himself against poisoning by taking less than lethal doses of poison on a regular basis. This practice came to be known as mithridatism. A universal antidote for a poison is sometimes referred to as a mithridate. Unfortunately for Mithridates, the practice of taking poisons actually worked against him in the end. During the 3rd Mithridatic War, Pompey the Great defeated Mithridates. Mithridates tried to poison himself instead of being captured but was unsuccessful becasue he had become tolerant of all the known poisons of his day. He instead had to stab himself with his own sword.
This strange ending of Mithridates' life is chronicled in a play called Mithridates, written in 1673 by Jean Racine. Mozart also wrote one of his first operas about the subject in 1770, Mitridate, re di Ponto.

Alabama Distribution:

Eupatorium compositifolium map

Photographs taken in Macon County, AL., 9-24-04, and off Lee Rd 10, Lee County, AL., 9-29-04.

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