The Joyful Botanist: I am Ironflower
Ironflowers are among the late summer/early fall flowering plants that provide important nectar and pollen to insects who are migrating south for the winter or preparing to overwinter here in the mountains.
Adam Bigelow photo
There is almost no flower in the Southern Mountains deeper in purple color than the ironflowers (Vernonia spp.) blooming now in unmown ditches and fallow fields all around Western North Carolina and across the Southeast.
Often interspersed with other late-summer wildflowers like goldenrods (Solidago spp.) and different asters (Symphyotrichum & Eurybia spp.), ironflowers stand tall in the meadow, dwarfed only by the queen-of-the-meadow herself, Joe-Pye flower (Eutrochium spp.).
Some readers might be thinking, isn’t this plant called ironweed? Yes, while most would use that name, I have shifted to swapping out the word “weed” with the word “flower” on native wildflowers that have the derogatory moniker. I’ve also begun adding the word “weed” to the ends of exotic invasive plants, like privet weed (Ligustrum spp.), multiflora rose weed (Rosa multiflora), and kudzu weed (Pueraria montana). To read more about this movement, see “The Joyful Botanist: Weeds are flowers too” from the Aug. 21 edition of The Smoky Mountain News.
To call such a beautiful and ecologically important native plant a weed is to invite people to kill it and keep it from growing, flowering and spreading. This is not good. Ironflowers are among the late summer/early fall flowering plants that provide important nectar and pollen to insects migrating south or preparing to overwinter here in the mountains. When considered as a weed, they are often chopped down in the name of order and cleanliness. And that’s too bad.
In addition to the many insects supported by its byproducts, ironflowers also provide host plant services to the American painted lady butterfly (Vanessa virginiensis), who use their leaves as a home and as food for their babies. The butterfly lays her eggs on the leaves of ironweed, and when the caterpillars hatch, they have their favorite food all around them. This and other host-plant relationships in nature like it, are one of the most important roles of native plants. Plants “eat” sunlight, caterpillars eat plant leaves, birds and other critters eat the caterpillars and energy is cycled up and into the ecosystem.
Ironflowers also help support the lives of native bees by having large hollow stems that persist through the winter and successive seasons. Many solitary, non-boring bees will use these stems to overwinter in safety and security. They will burrow into the stems after the seeds have been released, and the plant goes dormant for the winter. This is why it is important to reconsider the annual fall cleanup of a native plant garden, as the plant’s usefulness extends way beyond pretty flowers and seeds for the birds.
Related Items
The Joyful Botanist: Skeleton Trees
Headwaters plan sets conservation roadmap for Jackson County
REACH of Haywood County
The Joyful Botanist: Season of the Witch Hobble
Their importance goes beyond these utilitarian functions and interrelated evolutionary connections, however. I love them for their pure, vivid beauty. Roadsides and trails through meadows and forest edges are filled with their purple flowers. As a member of the composite group of the aster family (Asteraceae), many small individual flowers called florets comprise their flower heads.
Unlike sunflowers and asters, ironflowers are made up of disc flowers only and do not have ray flowers. If you picture a kid’s drawing of the sun, the disc flowers are where the smile would be, and the ray flowers emanate out from that central disc like the rays of the sun.
But ironflowers only have disc florets. These florets each have individual pistils and stamens (sexually reproductive parts of flowers) and provide pollen and nectar to the many bees, butterflies and moths who visit them.
And their flowers are purple. They often grow alongside goldenrods, whose flowers bloom a bright and vivid yellow. In her seminal work “Braiding Sweetgrass,” Robin Wall Kimmerer writes about being fascinated with why purple and gold flowers seemed to often grow together. It turns out that being opposite on the color wheel causes both flowers to stand out more to pollinating insects. When grown together, purple and gold flowers get more pollinator visits than research plots grown with just yellow or purple flowers.
While this purple and gold display is not the official story for Western Carolina University’s school colors (something about sunsets and majestic mountains), they do begin blooming together just in time for the start of the fall semester. Coincidence? I think not.
(The Joyful Botanist leads weekly wildflower walks most Fridays and offers consultations and private group tours through Bigelow’s Botanical Excursions. This email address is being protected from spambots. You need JavaScript enabled to view it.)
