Tephroseris palustris, commonly known as swamp ragwort, is a herbaceous plant that can be annual, biennial, or occasionally perennial. It is native to wetland habitats including marshes, stream banks, and slough areas across North America, particularly in regions with freezing winters. Swamp ragwort thrives in moist to wet soils found in damp meadows, swamps, sandy pond edges, and roadside ditches, at altitudes ranging from sea level to 3,300 feet. It typically stands 3 to 4 feet tall and is most noticeable when its bright yellow umbel flowers bloom from May to early July.

Swamp ragwort is valued for its vibrant yellow flowers that add color to wetland areas and its ability to thrive in moist soil conditions where other plants may struggle. It is often used in naturalistic plantings and wetland restoration projects. In cultivation, it requires consistently moist or wet soil and can tolerate full sun to part shade. While not commonly grown in traditional gardens, it serves an ecological role in supporting pollinators. Care should be taken as it can potentially spread in suitable conditions and may require management to prevent unwanted colonization.CC BY-SA 4.0