''Vernonia gigantea'' (also known as giant ironweed, tall ironweed or ironweed) is a species of

perennial plant A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

from family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

found in

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

. The plant is native to the eastern United States, north to New York state and Ontario, and southwest to Texas.

Description

They are described as tall, or . The

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

is either green or purplish green coloured, and can be either hairy or pubescent. The leaves are up to long and 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' bases may have a petiole or be

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

. The flowers open from July to September and are purple in colour. They can be found growing in moist

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

s along

roadside Roadside may refer to: *Road verge, a strip of greenery between a road and a sidewalk *Shoulder (road), an emergency stopping lane by the verge of a road *Roadside, Caithness, Scotland, a village * ''Roadside'' (film), a 2013 American horror film ...

s, and are common in

meadow A meadow ( ) is an open habitat, or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as these areas maintain an open character. Meadows may be naturally occurring or artifi ...

s and open

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

s. The seeds are wind-dispersed. The plant is

self-incompatible Self-incompatibility (SI) is a general name for several genetic mechanisms that prevent self-fertilization in sexually reproducing organisms, and thus encourage outcrossing and allogamy. It is contrasted with separation of sexes among individuals ...

and exhibits substantial

ecotypic variation In population genetics Population genetics is a subfield of genetics that deals with genetic differences within and between populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as Adaptation ...

, a factor which may explain their broad geographic distribution.

Ecology

''V. gigantea'' is a larval host to the

ironweed borer moth ''Papaipema cerussata'', the ironweed borer moth, is a moth in the family Noctuidae. It is found in eastern North America, where it has been recorded from Georgia, Illinois, Indiana, Kentucky, Maine, Maryland, Michigan, New Jersey, New York, No ...

(''Papaipema cerussata'') and the

red groundling moth ''Perigea xanthioides'', the red groundling moth or pied groundling moth, is a moth of the family Noctuidae. The species was first described by Achille Guenée in 1852. It is found from Canada to Brazil and on Jamaica. The wingspan is about 29& ...

(''Perigea xanthioides'').

References

External links

Vernonia gigantea
{{Taxonbar, from=Q1115547 gigantea Flora of the Northeastern United States Flora of the Southeastern United States Flora of the North-Central United States Flora of Texas Flora of Ontario Flora without expected TNC conservation status