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Marsh Ragwort

Senecio aquaticus

Please keep in mind that it is illegal to uproot a plant without the landowner's consent and care should be taken at all times not to damage wild plants. Wild plants should never be picked for pleasure and some plants are protected by law.
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Plant Profile

Flowering Months:
Asteraceae (Daisy)
Also in this family:
Alpine Blue Sow-thistle, Alpine Cotula, Alpine Fleabane, Alpine Saw-wort, Annual Ragweed, Annual Sunflower, Argentine Fleabane, Autumn Hawkbit, Autumn Oxeye, Beaked Hawksbeard, Beggarticks, Bilbao Fleabane, Black Knapweed, Black-eyed Susan, Blanketflower, Blue Fleabane, Blue Globe-thistle, Bristly Oxtongue, Broad-leaved Cudweed, Broad-leaved Ragwort, Brown Knapweed, Butterbur, Buttonweed, Cabbage Thistle, Canadian Fleabane, Canadian Goldenrod, Carline Thistle, Chalk Knapweed, Chamois Ragwort, Changing Michaelmas Daisy, Chicory, Chinese Mugwort, Chinese Ragwort, Coltsfoot, Common Blue Sow-thistle, Common Cat's-ear, Common Cudweed, Common Daisy, Common Dandelion, Common Fleabane, Common Goldenrod, Common Groundsel, Common Michaelmas Daisy, Common Mugwort, Common Ragwort, Common Wormwood, Coneflower, Confused Michaelmas Daisy, Corn Chamomile, Corn Marigold, Cornflower, Cotton Thistle, Cottonweed, Creeping Thistle, Daisy Bush, Dwarf Cudweed, Dwarf Thistle, Early Goldenrod, Eastern Groundsel, Eastern Leopardsbane, Elecampane, English Hawkweed, Fen Ragwort, Feverfew, Field Fleawort, Field Wormwood, Fox and Cubs, French Tarragon, Gallant Soldier, Garden Lettuce, Giant Butterbur, Glabrous-headed Hawkweed, Glandular Globe-thistle, Glaucous Michaelmas Daisy, Globe Artichoke, Globe-thistle, Goat's Beard, Golden Ragwort, Golden Samphire, Goldilocks Aster, Grass-leaved Goldenrod, Great Lettuce, Greater Burdock, Greater Knapweed, Grey-headed Hawkweed, Guernsey Fleabane, Hairless Blue Sow-thistle, Hairless Leptinella, Hairy Michaelmas Daisy, Harpur Crewe's Leopardsbane, Hawkweed Oxtongue, Heath Cudweed, Heath Groundsel, Hemp Agrimony, Highland Cudweed, Hoary Mugwort, Hoary Ragwort, Hybrid Knapweed, Intermediate Burdock, Irish Fleabane, Jersey Cudweed, Jerusalem Artichoke, Lance-leaved Hawkweed, Lavender-cotton, Leafless Hawksbeard, Least Lettuce, Leopardplant, Leopardsbane, Leptinella, Lesser Burdock, Lesser Hawkbit, Lesser Sunflower, London Bur-marigold, Magellan Ragwort, Marsh Cudweed, Marsh Hawksbeard, Marsh Sow-thistle, Marsh Thistle, Meadow Thistle, Melancholy Thistle, Mexican Fleabane, Milk Thistle, Mountain Everlasting, Mouse-ear Hawkweed, Musk Thistle, Narrow-leaved Cudweed, Narrow-leaved Hawkweed, Narrow-leaved Michaelmas Daisy, Narrow-leaved Ragwort, New England Hawkweed, New Zealand Holly, Nipplewort, Nodding Bur-marigold, Northern Hawksbeard, Norwegian Mugwort, Oxeye Daisy, Oxford Ragwort, Pearly Everlasting, Perennial Cornflower, Perennial Ragweed, Perennial Sow-thistle, Perennial Sunflower, Pineapple Mayweed, Plantain-leaved Leopardsbane, Ploughman's Spikenard, Plymouth Thistle, Pontic Blue Sow-thistle, Pot Marigold, Prickly Lettuce, Prickly Sow-thistle, Purple Coltsfoot, Rayed Tansy, Red Star Thistle, Red-seeded Dandelion, Red-tipped Cudweed, Robin's Plantain, Roman Chamomile, Rough Cocklebur, Rough Hawkbit, Rough Hawksbeard, Russian Lettuce, Safflower, Salsify, Saw-wort, Scented Mayweed, Scentless Mayweed, Sea Aster, Sea Mayweed, Sea Wormwood, Seaside Daisy, Shaggy Mouse-ear Hawkweed, Shaggy Soldier, Shasta Daisy, Shetland Mouse-ear Hawkweed, Shrub Ragwort, Sicilian Chamomile, Silver Ragwort, Slender Mugwort, Slender Thistle, Small Cudweed, Small Fleabane, Smooth Cat's-ear, Smooth Hawksbeard, Smooth Sow-thistle, Sneezeweed, Sneezewort, Spear Thistle, Spotted Cat's-ear, Spotted Hawkweed, Sticky Groundsel, Stinking Chamomile, Stinking Hawksbeard, Tall Fleabane, Tall Mouse-ear Hawkweed, Tansy, Thin-leaved Sunflower, Treasureflower, Trifid Bur-marigold, Tuberous Thistle, Tyneside Leopardplant, Viper's Grass, Wall Lettuce, Welsh Groundsel, Welted Thistle, White African Daisy, White Butterbur, White Buttons, Willdenow's Leopardsbane, Winter Heliotrope, Wood Burdock, Wood Ragwort, Woody Fleabane, Woolly Thistle, Yarrow, Yellow Chamomile, Yellow Fox and Cubs, Yellow Oxeye, Yellow Star Thistle, Yellow Thistle, York Groundsel
Life Cycle:
Biennial or Perennial
Maximum Size:
80 centimetres tall
Fens, grassland, marshes, riverbanks, riversides, waterside, wetland.

Yellow, many petals
Open clusters of bright yellow daisy-like flowerheads. Individual flowers up to 4cm. Inner bracts green and pointed with whiter edges. Outer bracts are much shorter than inner.
A smooth, cylindrical, ribbed achene (type of one-seeded fruit).
Deeply divided leaves with linear lobes. The leaves have blunt terminal lobes.
Scented leaves resembling the smell of Chrysanthemum.
Other Names:
Oak-leaved Ragwort, Water Groundsel, Water Ragwort.
Frequency (UK):
Occasionally seen  

Other Information


Senecio aquaticus, also known as water groundsel or marsh ragwort, is a perennial herb that is native to Europe and Asia. It is typically found in wetland environments, such as marshes, fens, and along the edges of streams and rivers. The plant has long, lance-shaped leaves and small yellow flowers that bloom in the summer. It can spread rapidly and is considered an invasive species in some areas, due to its ability to outcompete native plant species.


Marsh ragwort, also known as Senecio aquaticus, is a beautiful plant that can be found in wetlands, marshes, and along stream banks. This plant is a member of the Asteraceae family, which is the largest family of flowering plants in the world. Marsh ragwort is a perennial plant, which means that it lives for more than two years and it has a unique way of adapting to its environment.

One of the most distinctive features of marsh ragwort is its leaves. They are deeply lobed and can be up to 30 centimeters long. The leaves are also hairless and have a glossy, dark green appearance. The plant's stems can grow up to 120 centimeters in height and are hollow.

The flowers of marsh ragwort are a bright yellow color and bloom from July to September. They are arranged in small clusters, each containing around 8 to 20 flowers. The flowers are hermaphroditic, which means that they contain both male and female reproductive organs. This allows the plant to self-fertilize and reproduce even when pollinators are scarce.

Marsh ragwort is a common plant in wetlands and is an important part of the ecosystem. It provides food and habitat for a variety of wildlife, including insects, birds, and small mammals. The plant is also used in traditional medicine to treat a variety of ailments, including respiratory problems and digestive issues.

While marsh ragwort is a beautiful plant, it can be toxic to both humans and livestock if ingested in large quantities. The plant contains pyrrolizidine alkaloids, which can cause liver damage and other health problems. It is important to be cautious when handling this plant and to avoid ingesting any parts of it.

Marsh ragwort is a fascinating plant that is well adapted to living in wetland environments. Its unique features, including its deeply lobed leaves and bright yellow flowers, make it a beautiful addition to any wetland ecosystem. However, it is important to be aware of its potential toxicity and to handle it with care.

Marsh ragwort is a widespread plant that can be found throughout much of Europe and parts of Asia. It is typically found in wetlands and areas with high moisture, such as near streams and rivers, marshes, and swamps. It is well adapted to these environments and is able to thrive in areas where other plants may struggle to survive.

One of the reasons marsh ragwort is able to adapt to wetland environments is because it has a unique root system. The plant has a thick, fleshy root that is able to store water and nutrients, which helps it survive in areas with high moisture. The roots are also able to absorb nutrients and water from the soil, which helps the plant grow and thrive.

In addition to its adaptation to wetland environments, marsh ragwort has also been used for medicinal purposes for centuries. In traditional medicine, the plant has been used to treat a variety of ailments, including respiratory problems, digestive issues, and skin irritations. The plant contains a number of compounds that are thought to have medicinal properties, including flavonoids, tannins, and sesquiterpene lactones.

Despite its medicinal properties, marsh ragwort can be toxic if ingested in large quantities. The plant contains pyrrolizidine alkaloids, which can cause liver damage and other health problems if consumed in large amounts. For this reason, it is important to use caution when handling the plant and to avoid ingesting any parts of it.

Marsh ragwort is a fascinating plant that is well adapted to wetland environments. Its unique features and medicinal properties make it an important part of the ecosystem and a valuable resource for traditional medicine. However, it is important to be aware of its potential toxicity and to handle it with care. By understanding the unique characteristics and uses of marsh ragwort, we can better appreciate this beautiful and complex plant.

In addition to its ecological and medicinal significance, marsh ragwort also has cultural and historical importance. In some European countries, the plant has been used for centuries in traditional herbal remedies and folklore. For example, in the Czech Republic, marsh ragwort is used to ward off evil spirits and protect against sorcery.

In the past, the plant was also used for textile dyeing. The yellow flowers were used to dye wool and other textiles, creating a bright and beautiful color. However, this practice has declined in recent years due to the plant's toxicity and the availability of synthetic dyes.

Despite its many benefits, marsh ragwort can also be an invasive species in some areas. It can grow rapidly and displace native plants, which can have negative impacts on the local ecosystem. In some areas, efforts are being made to control the spread of the plant and prevent it from becoming a problem.

Marsh ragwort is a unique and interesting plant with many ecological, medicinal, and cultural benefits. It is a valuable part of the wetland ecosystem and has been used for centuries in traditional medicine and textile dyeing. However, it is important to be aware of its potential toxicity and to handle it with care. By understanding the many uses and characteristics of marsh ragwort, we can better appreciate and protect this important plant.

Marsh ragwort is also an important food source for some insects, including moths and butterflies. The caterpillars of the cinnabar moth, for example, feed exclusively on the leaves of marsh ragwort. These caterpillars are brightly colored and can be seen feeding on the plant during the summer months. The cinnabar moth is a common sight in wetlands and other areas where marsh ragwort grows.

Another interesting feature of marsh ragwort is its ability to tolerate flooding. The plant is able to survive in areas that are inundated with water for extended periods of time. It does this by adapting its growth habits, such as elongating its stems to reach the water's surface or growing leaves that are more resistant to water damage.

In recent years, there has been increasing interest in the use of marsh ragwort as a bioindicator of wetland health. Bioindicators are organisms that are used to assess the health of an ecosystem. Because marsh ragwort is so well adapted to wetland environments, it can be used to monitor changes in water quality, nutrient levels, and other environmental factors.

Overall, marsh ragwort is a fascinating plant with many interesting and important features. It plays a vital role in wetland ecosystems and has been used for centuries in traditional medicine and textile dyeing. While it is important to be aware of its potential toxicity, the many benefits of this plant make it a valuable part of our natural world.

Distribution Map

Reproduced by kind permission of the BSBI.

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