Vernonia arkansana DC.

Taxonomy and Common Names

Vernonia arkansana DC., commonly called Arkansas ironweed or great ironweed, is a perennial plant species in the Asteraceae family. It is native to the south-central United States.

Size and Growth Habit

Mature plants grow 1.2–1.8 meters (4–6 feet) tall and spread 0.91–1.22 meters (3–4 feet) wide. Its pink-purple flowers bloom from August to September.

Cultivar Recognition

The cultivar 'Mammuth' has received the Royal Horticultural Society's Award of Garden Merit.

Pollinators and Nectar Collectors

In its ecology, this plant is pollinated by a variety of insects including bees, butterflies, and skippers, which also collect nectar from it. The specialist bee Melissodes vernoniae is a frequent visitor to all Vernonia species, including this one.

Herbivorous Insects

The aphid Aphis vernoniae is specifically attracted to this plant species and prefers to feed on its sap. Various moth caterpillars also feed on the plant.

Herbivory Avoidance by Vertebrates

Birds do not feed on it, due to its hard seeds and the low volume of pollen available that would suit hummingbirds. Herbivorous mammals also avoid the plant because its foliage is bitter.