|Photo taken by Gil Nelson|
|Division:||Magnoliophyta – Flowering plants|
|Class:||Magnoliopsida – Dicotyledons|
|Family:||Asteraceae ⁄ Compositae|
| Vernonia gigantea|
|Natural range of Vernonia gigantea from USDA NRCS Plants Database.|
Common names: Giant ironweed, Common ironweed
Synonyms: Vernonia gigantea var. gigantea; Vernonia altissima var. altissima; Vernonia gigantea (Walter) Trelease ssp. gigantea; Vernonia altissima Nuttall; Vernonia altissima var. taeniotricha S.F. Blake
A description of Vernonia gigantea is provided in The Flora of North America.
In the Coastal Plain, V. gigantea has been found in loam soil atop of a ravine; loamy sand in mesic hardwoods; river hammocks; marshes; floodplain forests; upland mixed forest; shortleaf pine-post &red oak-mockernut woods; pine-oak-hickory woods in a ravine; annually burned upland pineland; calcareous slopes; sandy loam in mature hardwoods; sandy open live oak hammocks; sand beneath cabbage palm thicket; calcareous mixed flatwoods hammocks; hammock surrounded by marsh; lowland forests habitats; and sandy peat in a clearing of cabbage palm-live oak hammock.   It is found in disturbed successional areas  along with moist loam of roadside depressions; loamy sand along edge of channel; open mixed hardwood forest between power-line and road; along powerline corridors; and grassy clearings of pine-palmetto flats. Substrate types include loam, loamy sand, sandy loam, calcareous soils, limestone, sand, and sandy peat. 
Associated species include Eupatorium fisulosum, Arnoflossum ovatum, Smilax bona-nox, Morus rubra, Campsis radicans, and cabbage palm. 
It has been observed flowering January through November and fruiting June through November. 
Seed bank and germination
Heating at low temperatures stimulates germination in V. gigantea. 
It has been observed to thrive after low-intensity fires. 
Conservation and management
Cultivation and restoration
References and notes
- Emery, S. M., J. Uwimbabazi, et al. (2011). "Fire intensity effects on seed germination of native and invasive Eastern deciduous forest understory plants." Forest Ecology and Management 261: 1401-1408.
- Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Loran C. Anderson, Robert K. Godfrey, Robert L. Lazor, Gary R. Knight, R. Kral, P. L. Redfearn, Jr., R. F. Thorne, R. A. Davidson, Brenda Herring, Don Herring, R. A. Norris, Andre F. Clewell, Sidney McDaniel, R. Komarek, Lisa Keppner, S. W. Leonard, Richard S. Mitchell, D. S. Correll, Grady W. Reinert. States and Counties: Florida: Brevard, Calhoun, Citrus, Dixie, Escambia, Flagler, Franklin, Gadsden, Gilchrist, Gulf, Jackson, Jefferson, Leon, Levy, Liberty, Madison, Nassau, Polk, Putnam, Seminole, St. Johns, Suwannee, Taylor, Wakulla, Washington. Georgia: Thomas. Mississippi: Holmes. Compiled by Tall Timbers Research Station and Land Conservancy.