Swamp Thistle is a native biennial thistle adapted to wet habitats, growing 3–8 feet tall in marshes, fens, and wet meadows across eastern North America. It produces numerous small, rosy-purple flower heads that bloom in late summer. Unlike most thistles, the bracts of Swamp Thistle lack prominent spines — the specific epithet 'muticum' means 'blunt' or 'lacking a point.' It is an important native plant supporting native bees and butterflies.
Habitat
Found in marshes, fens, wet meadows, and boggy stream margins in eastern North America.
Diet
Provides nectar for bumblebees and specialist thistle bees; seeds consumed by goldfinches.
How common
Uncommon
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