Above: Swamp Thistle near cattails along shore of Lake Wingra along Arboretum Drive in Madison, Wisconsin (8/16/22).
Swamp Thistle - Cirsium muticum
Swamp Thistle is a native thistle that grows in wet areas like shores, fens, meadows, streamsides, and swamps.
Swamp Thistle grows 4' to 7' tall.
Swamp Thistle flowers are pink to purple in color and are about 1 - 1 1/2" wide. The bracts are typically spineless. A distinctive feature of Swamp Thistle is that there is a fuzzy/cottony webbing between the bracts.
Blooms: July to October.
Above: Swamp Thistle leaves are deeply lobed and widely spaced on the stem. Photo taken on August 22, 2022.
For more information on Swamp Thistle, visit Wikipedia.
Or, visit the UW-Madison Wisconsin State Herbarium website page about Swamp Thistle.
Swamp Thistle
Cirsium muticum
Above: Bee on Swamp Thistle near cattails along shore of Lake Wingra along Arboretum Drive in Madison, Wisconsin on August 22, 2022.
Above: Bee on Swamp Thistle near cattails along shore of Lake Wingra along Arboretum Drive in Madison, Wisconsin on August 17, 2022.
Above: Swamp Thistle near cattails along shore of Lake Wingra along Arboretum Drive in Madison, Wisconsin on August 16, 2022.
Above: Swamp Thistle in UW Arboretum's Curtis Prairie in Madison, Wisconsin on September 9, 2022.
Above: Swamp Thistle in UW Arboretum's Curtis Prairie in Madison, Wisconsin on September 27, 2022.
Above: 1913 Swamp Thistle (Cirsium muticum) drawing.
Above: Swamp Thistle (Cirsium muticum) botanical illustration from Wild Flowers of New York circa 1918.
Above: Swamp Thistle (Cirsium muticum) specimen collected in Wauwatosa, Wisconsin on September 19, 1937. Specimen was 5 feet tall.
Above: Swamp Thistle (Cirsium muticum) specimen collected in in Kewaunee County, Wisconsin on September 27, 2011.