Above: Tall Ironweed in drainage ditch along bikepath between Midvale Blvd. and the Beltline in Madison, Wisconsin. (9/14/20).
Tall Ironweed - Vernonia gigantea/Vernonia altissima
Tall Ironweed is not common in Wisconsin and is not referenced on the USDA U.S. Forest Service map as being a Wisconsin native.
Tall Ironweed grows from 5 feet - 9 1/2 feet tall. The plants photographed in Madison, Wisconsin were within this height range with most reaching 9 feet in height.
The plants were growing in a drainage ditch along an old railroad track converted to a bke path.
The central stem is light green or purplish green. The flowers are purple/magenta and blooms from late July through September. The nectar of the flowers attracts butterflies, skippers, and various bees.
Personal note: I've never seen so many Monarch Butterflies in such a concentrated area in Wisconsin. There were hundreds of Monarchs alighting on Tall Ironweed blossoms all within 50 yards.
Other names: Giant Ironweed, Ironweed.
Above: Tall Ironweed stalk along bikepath between Midvale Blvd. and the Beltline in Madison, Wisconsin. (9/20/20).
NOTE: Common Ironweed (Vernonia fasciculata) is native to Wisconsin. It is a smaller plant with thinner leaves.
For more information on the Tall Ironweed, visit Wikipedia.
Or, visit the UW-Madison Wisconsin State Herbarium website page about Common Ironweed - Vernonia fasciculata.
Ironweed
Vernonia gigantea
Above: Tall Ironweed along bikepath behind Gregory Street near Commonwealth Ave. in Madison, Wisconsin. (8/3/1).
Above: Tall Ironweed in drainage ditch along bikepath between Midvale Blvd. and the Beltline in Madison, Wisconsin. (9/14/20).
Above: Tall Ironweed in drainage ditch along bikepath between Midvale Blvd. and the Beltline in Madison, Wisconsin. (9/15/20).
Above: Ironweed (Vernonia noveboracensis) illustration by Alice Lounsberry circa 1899.
Above: Ironweed.