Yellow Marsh Marigold - Caltha palustris L.
Above: Yellow Marsh Marigold along the shore of Ho-Nee-Um Pond along boardwalk in UW Arbortetum in Madison, Wisconsin (4/24/23).
Yellow Marsh Marigold - Caltha palustris L. (Ephemeral)
Yellow Marsh Marigold is a native mounded perennial that grows 8" - 24" tall in wet areas like meadows, marshes, pond and streambanks. The plant goes dormant after blooming and the entire plant can die to the ground by the heat of mid-summer.
Yellow Marsh Marigold is part of the Ranunculaceae family (Buttercup). Its yellow flowers resemble large buttercups more than marigolds. They are 5-9-parted, rounded petal-like sepals with distinct veins radiating from the base. The flowers are between 1/2"-1 1/2" wide.
Careful, this plant is considered hazardous! The leaves of Marsh Marigold contain an oily toxin called protoanemonin (that is found in all plants of the Ranunculaceae family) and can cause skin irritation.
Blooms April to May.
Other names: Cowslip, Marsh-marigold, Kingcup.
Caltha palustris – comes from Latin where calathos is a cup, and palustris means "of swamps."
Above: Marsh Marigold leaves are mostly basal, round to kidney-shaped and heart-shaped (they are not divided).
Yellow Marsh Marigold is sometimes confused with Lesser celandine which is a prohibited species under the Wisconsin's invasive species rule. Lesser celandine (Ranunculus ficaria) is not common in Wisconsin.
Above: Back of Marsh Marigold flower. NOTE: Lesser celandine has 7 to 11 yellow petals and 3 green sepals below the petals; whereas, Marsh Marigold flowers do not (see above). In fact, Marsh Marigold flowers do not have petals, but rather yellow, petal-like sepals. Also, Marsh Marigold does not produce tubers or bulblets like Lesser Celandine.
For more information on the Yellow Marsh Marigold, visit Wikipedia.
Or, visit the UW-Madison Wisconsin State Herbarium website page about Marsh Marigold - Caltha palustris L..
Or, visit the USDA U.S. Forest Service Plant of the Weekwebsite page about Yellow Marsh Marigold.
Yellow Marsh Marigold
Caltha palustris L.
Above: Back of Marsh Marigold blossom (4/25/23).
Above: Marsh Marigold plants on shore of Ho-Nee-Um Pond in UW Arboretum in Madison, Wisconsin (4/27/23).
Above: 1913 illustration of Yellow Marsh Marigold.
Above: Yellow Marsh Marigold botanical line drawing from USDA NRCS, Wetland flora: Field office illustrated guide to plant species. USDA NRCS National Wetland Team.
Above: Marsh Marigold (Caltha palustris) botanical painting by Mary Vaux Walcott circa 1924.
Above: Yellow Marsh Marigold botanical drawing circa 1885.
Above: Yellow Marsh Marigold botanical illustration by Carl Axel Magnus Lindman circa 1917 - 1926.
Don't Confuse native Marsh Marigold with invasive Lesser Celandine.
Above: Video on identifying Lesser Celandine that is often confused with the native Marsh Marigold.
Above: Comparison image of Marsh Marigold vs. Lesser Celandine from The Natural Resources Conservation Service (NRCS).
