|Tall ironweed near Cincinnati, OH|
Vernonia gigantea (also known as giant ironweed, tall ironweed or ironweed) is a species of perennial plant from Asteraceae family that can be found in United States and Canada. The plant is native to the eastern United States, north to New York state and Ontario, and southwest to Texas.
They are described as 3–7 feet tall, or 5-10 by 1-2 feet. The stem is either green or purplish green coloured, and can be either be hairy or pubescent. The leaves are up to 10 inches long and 2½ inches across, and are ovate. Their leaves could also be lanceolate-oblong or elliptically shaped, with serrated margins. The leaves' upper surface is hairless and is dark green in colour. The leaves' base has either a petiole or sessile. The flowers bloom from July to September and are purple coloured. They can be found growing in moist soils by the roadsides, and are common in the meadows and open woodlands.
- "Vernonia gigantea". USDA. PLANTS Profile. Retrieved September 7, 2012.
- Common names
- "Vernonia gigantea - Ironweed". Goodness Grows. Retrieved September 7, 2012.
- "Tall Ironweed". Illinois Wild Flowers. Retrieved September 7, 2012.
- Urbatsch, Lowell (1973). "A Study Of Ecotypes In Vernonia Gigantea Gigantea (Compositae)". Transactions of the Nebraska Academy of Sciences and Affiliated Societies. p. 188. Retrieved 10 October 2015.