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IRONWEED, TALL
Vernonia altissima

Tall ironweed infesting farm pasture.

Tall ironweed flowers.

Tall ironweed infesting a no-till corn field.



  • The genus name 'Vernonia' was given in honor of William Vernon, an English botanist who worked in North America.

  • 'Ironweed' refers to the toughness of the stem and the fact that it is very difficult to dig up this species with a shovel.

  • Native Americans used the root to relieve pain.

  • Tall ironweed is the third most troublesome pasture weed in Kentucky, and it is becoming increasingly prevalent as a weed in Ohio.