SafePlants

Marsh Thistle (Cirsium palustre)

Cirsium palustre, commonly known as marsh thistle or European swamp thistle, is a biennial or perennial herbaceous species belonging to the genus Cirsium.

Taxonomy and Nomenclature

• Scientific Name: Cirsium palustre (L.) Scop.
• Common Names: Marsh thistle, European swamp thistle, marsh plume thistle, European marsh thistle, Eurasian marsh thistle.
• Synonyms: Carduus palustris.
• Family: Daisy Family (Compositae or Asteraceae), subfamily Carduoideae.

Distribution and Habitat

• Found throughout Europe to central Asia.
• Common in damp environments such as mires, fens, marshes, damp grasslands, rush-pastures, wet woodlands, and montane springs.
• Common weed in Britain, thriving in damp woodland, meadows, and marshes, particularly on acid soils.
• Present in The Western Isles (Scotland) along with Spear Thistles and Creeping Thistles.
• Found in marsh thistle meadows, specifically Sub-Atlantic wet grasslands of brook banks and soggy slopes of rainy granitic and crystalline hills and low mountains of middle Europe.
• Observed in New York.

Ecological Role

• Can become very invasive in grassland.
• Aggressively colonizes natural areas, decreases biodiversity, and compromises the ecological integrity of an area when introduced.

Morphological Characteristics and Growth Habits

• Herbaceous biennial or perennial, growing up to 2 meters (approximately 6.5 feet) tall, and in some cases up to 8 feet tall.
• Tall, erect plant, usually with a single main stem.
• The stem is winged and armed with spines. Spine-edged, leafy wings are present on the stem.
• Flowerheads are in groups and up to 1.5 cm in size.
• Florets are reddish-purple.
• Relatively easy to identify by the absence of strong spiny-tips on the phyllaries.
• Distinguished from Welted Thistle by its feathery seeds (Welted Thistle has seeds with unbranched down).

Interactions with Other Organisms

• Visited by at least 80 species of bee, butterfly, and fly.
• Serves as a food source for various moths, including Aethes cnicana and Epiblema cirsiana.
• A Peacock Butterfly (Inachis io) has been observed on Marsh Thistle.

Resources and Further Information

• Royal Horticultural Society (RHS)
• Down Garden Services
• APHOTOFLORA - Photographic Stock Library
• SUNY College at Oneonta
• English Wiktionary
• abinvasives.ca