Ironweed

September 12, 2022

As Melissa and I were leaving town last week we passed a brilliant magenta flower along the side of the road just out of the mow zone.  I gave a shout, but we had already driven past, and I was unable to get a picture.  When I asked her to turn around, Melissa initially balked wanting to get home, but then relented.  We circled back and saw it, making a U-turn so I could get the picture from my side of the car.  Melissa suggested I might want to hurry as there were people standing in the yard watching what we were doing.  I took the photo, waved at the family, and we took off toward home.  When I pulled the plant up on my Google app it was identified as ironweed.

When I looked online, I found Vernonia is a genus of about 350 species of forbs and shrubs in the family Asteraceae (daisy) and those species known as ironweed have intense purple flowers.  The genus is named for the English botanist William Vernon.  There have been numerous distinct subgenera and subsections named in this genus, and some botanists have divided the genus into several distinct genera.  Vernonia arkansana (also known as Arkansas ironweed and great ironweed) is native from Illinois to Kansas south to Arkansas and Oklahoma.  The plant is 4 to 6 feet (1.2 to 1.8 m) high and 3 to 4 feet (0.91 to 1.22 m) wide.  The flowers bloom from August to September and are pink-purple in color.  The plant is pollinated by various insects such as bees, butterflies, and skippers, who also collect nectar.  The species also attracts an aphid (Aphis vernoniae) that prefers to suck on juice of the species, and various moth caterpillars.  Birds avoid the species due to hard seeds, as do mammal herbivores due to the bitterness of its foliage.  Since it was in town, it probably did not have to worry about cows anyway.

Arkansas ironweed is commonly called curlytop ironweed and typically occurs in gravel and sand bars along streams, slough margins, wet meadows, thickets, open woods, prairies, and glades.  This plant is noted for its narrow, willow-like leaves, large flowering heads, and its narrow, twisting, involucral bracts (a modified leaf for reproduction).  The source of the common name for Vernonia has been varyingly attributed to certain “iron-like” plant qualities including tough stems, rusty-tinged fading flowers, and rusty colored seeds.  Except for its brilliant flowers (does it need more?) the plant is a somewhat unremarkable ornamental.  This plant spreads aggressively by rhizomes (bulbs) to form clumps and is often categorized as a pasture weed.  The seeds are wind-dispersed and will readily self-hybridize with other Ironweed species which can make plant ID difficult in the field.  While I could not identify the exact species, the size, date of flowering, and location suggested this was an Arkansas Ironweed.

𝗧𝗛𝗢𝗨𝗚𝗛𝗧𝗦:  When I saw the family in the yard as I took a picture of the Ironweed it reminded me of when I worked for State History of Utah.  One of my jobs was architectural survey and I would drive up and down the streets of small towns taking pictures and recording characteristics of the buildings to be entered into a computer database.  I was stopped several times by the local police asking what I was doing but the best responses were when I caught someone working on their house.  As I snapped the picture I would hear, “I was going to get my permit tomorrow!”  I would wave and drive on.  As we drove off after taking the picture of the ironweed, I realized the man was building a fence for his horse which was standing in the front yard.  I wonder if he had a permit.  Act for all. Change is coming and it starts with you.