Curlytop or Arkansas Ironweed

Vernonia arkansana

Among the beautiful purple flowers of all the ironweeds in Arkansas, this one stands out as particularly striking. Its bright magenta flowers, perched atop their twisting, curly phyllaries, create a unique and impressive blossom that truly sets it apart from any other flower. An uncommon plant to find in nature, this beauty is worth seeking out to add to your native garden or into a restoration project.


  1. NAME
  2. BLOOM
  3. POLLINATORS
  4. DESCRIPTION
  5. PLANTS GROWING NEARBY
  6. HABITAT
  7. CONSERVATION STATUS
  8. INTERESTING TIDBITS

The genus Vernonia was named after William Vernon, an English botanist who traveled and collected plants in Maryland during 1698. The specific epithet arkansana, on the other hand, refers to the state of Arkansas, where this plant is particularly dominant, especially in the Arkansas Ozarks. Commonly known as Curlytop ironweed or Arkansas ironweed, this plant is characterized by its prominently curled, thread-like bracts found at the base of each flower. The name ‘Curlytop’ aptly describes this distinctive feature, while the common name ‘Arkansas’ ironweed highlights its widespread presence in the state.


Vernonia arkansana has large flowers, exceeding those of other ironweeds. Each flowerhead is about an inch wide (or more) and consists of 50 to 100 bright magenta florets. The florets have 5 lobes with long exserted, bifurcated styles brushed with white pollen.

  • Curled phyllaries
    Curled phyllaries
  • White pollen
    White pollen
  • Style with 2 branches
    Style with 2 branches
  • Styles and phyllaries
    Styles and phyllaries
  • Flower head and spent flower
    Flower head and spent flower
  • Late stage flowering
    Late stage flowering

Curlytop ironweed is a perennial native wildflower growing to about 4 to 5 ft tall. Like all ironweeds, it is prone to hybridize with other nearby ironweeds. The narrow leaves are alternate, oval and sessile (occasionally with short petioles). They are glabrous to slightly hairy. The stem is typically glabrous, occasionally with some hairs near the tip.

  • Graceful early leaves
    Graceful early leaves
  • Stem, leaves, buds and flowers
    Stem, leaves, buds and flowers
  • Flowers in many stages
    Flowers in many stages
  • Slender leaves and spent flower heads
    Slender leaves and spent flower heads

After flowering, fluffy, soft brown seed heads appear. The seed heads are quite beautiful and attract birds such as Goldfinches, Sparrows, and Juncos.

  • Ripe seed heads
    Ripe seed heads
  • Fluffy seed head
    Fluffy seed head

Bees, wasps, butterflies and skippers are all visitors to these unique flowers.

  • American bumble bee
    American bumble bee
  • Melissodes bee
    Melissodes bee
  • Sachem skipper
    Sachem skipper
  • Sleepy orange butterfly
    Sleepy orange butterfly

I've also noted a very tiny Braconid wasp visiting the flowers.

  • Braconid wasp
  • Braconid wasp

I often find Gray-headed coneflower (Ratibida pinnata) and Black-eyed Susan (Rudbeckia hirta) growing near Curlytop ironweed when it's growing in grassland habitat.

  • With Ratibida pinnata
    With Ratibida pinnata
  • With Rudbeckia hirta
    With Rudbeckia hirta

Take a look at the Growing Nearby section to see other native companions.


Vernonia arkansana is found in a variety of habitats from open woods, bottomland forests and prairies, gravel and sand bars along streams and fens, and occasionally glades.

  • Gravel and sand bar
    Gravel and sand bar
  • Woodland edge
    Woodland edge
  • Prairie
    Prairie
  • Glade
    Glade

Arkansas ironweed is found in Arkansas, Missouri, Kansas and Oklahoma. It is not well documented on NatureServe. It is listed as Vulnerable in Kansas with all other states within its range showing No Status Rank.

In Arkansas, Vernonia arkansana has a C-value of 7 in the group of 4-7, meaning "Typically matrix taxa in intact, stable habitats, with some limited ability to respond to destabilizing forces and repopulate areas from which they have been extirpated."


This is a terrific plant for a native garden as it rarely flops and invites many interesting insects. On top of that, it is not browsed by deer and other herbivores due to its bitter taste.