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Great Fen Sedge

Cladium mariscus

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:
Cyperaceae (Sedge)
Also in this family:
American Galingale, Birdsfoot Sedge, Black Alpine Sedge, Black Bog-rush, Bladder Sedge, Bog Sedge, Bottle Sedge, Bristle Club-rush, Bristle Sedge, Broad-leaved Cotton-grass, Brown Beak-sedge, Brown Bog-rush, Chestnut Rush, Close-headed Alpine Sedge, Club Sedge, Common Club-rush, Common Cotton-grass, Common Sedge, Common Spike-rush, Curved Sedge, Deergrass, Dioecious Sedge, Distant Sedge, Divided Sedge, Dotted Sedge, Downy-fruited Sedge, Dwarf Sedge, Dwarf Spike-rush, Estuarine Sedge, False Fox Sedge, False Sedge, Few-flowered Sedge, Few-flowered Spike-rush, Fibrous Tussock Sedge, Fingered Sedge, Flat Sedge, Flea Sedge, Floating Club-rush, Gingerbread Sedge, Glaucous Sedge, Greater Pond Sedge, Greater Tussock Sedge, Green-ribbed Sedge, Grey Club-rush, Grey Sedge, Hair Sedge, Hairy Sedge, Haresfoot Sedge, Hare's-tail Cotton-grass, Heath Sedge, Hop Sedge, Large Yellow Sedge, Lesser Pond Sedge, Lesser Tussock Sedge, Long-bracted Sedge, Many-stalked Spike-rush, Mountain Bog Sedge, Needle Spike-rush, Northern Deergrass, Northern Spike-rush, Oval Sedge, Pale Sedge, Pendulous Sedge, Perennial Sedge, Pill Sedge, Prickly Sedge, Remote Sedge, Rock Sedge, Round-headed Club-rush, Russet Sedge, Salt Sedge, Sand Sedge, Scorched Alpine Sedge, Sea Club-rush, Sheathed Sedge, Slender Club-rush, Slender Cotton-grass, Slender Sedge, Slender Spike-rush, Slender Tufted Sedge, Smooth-stalked Sedge, Soft-leaved Sedge, Spiked Sedge, Spring Sedge, Star Sedge, Starved Wood Sedge, Stiff Sedge, String Sedge, Sweet Galingale, Tall Bog Sedge, Tawny Sedge, Thin-spiked Wood Sedge, Triangular Club-rush, True Fox Sedge, Tufted Sedge, Water Sedge, White Beak-sedge, White Sedge, Wood Club-rush, Wood Sedge, Yellow Sedge
Life Cycle:
Maximum Size:
2 metres tall
Fens, gardens, marshes, riverbanks, riversides, swamps, waterside, wetland.

Brown, no petals
Clusters of light brown, short-stalked spikelets in long-stalked umbels. The individual flowers are egg-shaped.
The dark brown fruits measure a maximum of 3mm each. The seeds ripen in August and September.
A patch-forming perennial with stiff, glaucous leaves and saw-toothed edges. The leaves are V-shaped in cross section and up to 15mm wide.
Other Names:
Elk Sedge, Jamaica Swamp Sawgrass, Saw Grass, Saw-sedge, Sawtooth Sedge, Swamp Sawgrass, Twig-rush.
Frequency (UK):
Occasionally seen  

Other Information


Cladium mariscus, also known as sawgrass or twig-rush, is a species of rush that is native to wetlands in Europe, Asia and North America. It is a perennial herb that can grow up to 2 meters tall. It typically grows in wetland habitats such as marshes, fens, and along the margins of lakes and rivers. It is also commonly found in coastal saltwater marshes and swamps. The leaves are long and narrow, and the flowers are small and arranged in spikes. The fruit is a small achene. This species is a valuable plant in wetland ecosystem and it's important for wildlife habitat, water quality and erosion control. Sawgrass is also used in landscaping, ornamental horticulture and as a natural material for crafts and baskets. It is also a major component of the Everglades ecosystem in Florida, USA.


Great Fen Sedge (Cladium mariscus) is a perennial plant species that is native to Europe and parts of Asia. It is a member of the sedge family (Cyperaceae) and is commonly found growing in wetland habitats such as marshes, fens, and swamps.

Great Fen Sedge is a tall and robust plant that can grow up to 2 meters (6.5 feet) in height. It has long, narrow leaves that can reach up to 2 centimeters (0.8 inches) in width and are sharp and prickly to the touch. The stems of the plant are sturdy and upright, and are often covered in a layer of rough and fibrous sheaths.

One of the most distinctive features of Great Fen Sedge is its flowering spike, which emerges in late summer and can reach up to 50 centimeters (20 inches) in length. The spike is made up of small, brownish flowers that are arranged in clusters along the stem. The flowers are wind-pollinated, and the plant produces large quantities of small, dry seeds that are dispersed by the wind.

Great Fen Sedge is an important plant species for wetland ecology. It is highly adapted to wetland habitats, and its extensive root system helps to stabilize wetland soils and prevent erosion. The plant also provides habitat and food for a variety of wetland animals, including birds, insects, and small mammals.

Great Fen Sedge has a long history of use by humans. The tough, fibrous leaves of the plant have been used for centuries to make a variety of traditional crafts, including baskets, mats, and thatching for roofs. The plant has also been used for medicinal purposes, and was traditionally used to treat a variety of ailments including fever, kidney problems, and digestive disorders.

Today, Great Fen Sedge is an important plant species for wetland conservation and restoration efforts. It is often used in wetland restoration projects to help stabilize soils and promote the growth of other wetland species. Great Fen Sedge is also a popular plant for use in ornamental gardens, where its distinctive appearance and adaptability to wet soils make it a unique and attractive addition.

Great Fen Sedge is a fascinating and important plant species that plays a crucial role in wetland ecology and conservation. Its distinctive appearance, ecological importance, and long history of human use make it a species of great interest and significance. As wetland habitats continue to face increasing threats from development and climate change, it is more important than ever to understand and appreciate the value of species like Great Fen Sedge in maintaining the health and integrity of these vital ecosystems.

Great Fen Sedge is a plant species that is adapted to growing in wetland habitats with fluctuating water levels, and it can tolerate both inundation and drought. It is typically found in areas with shallow water, and it can grow in water up to 30 centimeters (12 inches) deep.

Great Fen Sedge is a slow-growing plant species that can take several years to reach maturity. It reproduces vegetatively, meaning that new plants grow from the rhizomes or roots of existing plants. The plant can also reproduce sexually, with flowers that produce small, dry seeds that can be dispersed by the wind.

The habitat where Great Fen Sedge is found, wetlands, are increasingly threatened by human activities such as drainage for agriculture, urban development, and peat extraction. As a result, the plant's population has declined significantly in many areas. In response to these threats, conservation efforts have been initiated to protect and restore wetland habitats, and Great Fen Sedge is a key component of many of these efforts.

Great Fen Sedge has also been the subject of scientific research, and its unique properties and adaptations have made it of interest to scientists studying wetland ecology and plant physiology. Studies have shown that the plant can store large amounts of carbon in its tissues, which makes it an important component of wetland carbon sequestration efforts.

In addition to its ecological and scientific significance, Great Fen Sedge is also valued for its cultural and historical importance. It has been used by humans for centuries, and its tough, fibrous leaves have been used to make a variety of traditional crafts. In many areas, Great Fen Sedge is also an important part of local folklore and has been associated with the supernatural or the spiritual.

Great Fen Sedge is a plant species with a rich and diverse history. Its ecological importance, cultural significance, and unique adaptations make it an important and fascinating plant species to study and conserve. As we continue to face growing threats to our wetland habitats, it is essential to understand and appreciate the value of species like Great Fen Sedge in maintaining the health and resilience of these important ecosystems.

Great Fen Sedge is also an important component of the biodiversity of wetland ecosystems. Wetlands are among the most biologically diverse ecosystems on the planet, and they support a wide variety of plant and animal species. Great Fen Sedge provides habitat and food for a range of wetland animals, including insects, birds, amphibians, and small mammals. It also helps to support a healthy ecosystem by stabilizing soils, reducing erosion, and regulating water flow.

Conservation efforts for Great Fen Sedge and other wetland plant species typically focus on habitat restoration and management. Restoration involves restoring degraded wetlands to their natural state, which can involve measures such as removing invasive species, planting native species, and managing water levels. Management involves ongoing efforts to maintain the health and biodiversity of wetland habitats, which can include measures such as controlled burns, mowing, and invasive species removal.

Great Fen Sedge is also a valuable plant species for use in phytoremediation. Phytoremediation is a process that uses plants to remove contaminants from the environment, and wetland plants such as Great Fen Sedge are particularly effective at removing pollutants from water and soil. In this way, Great Fen Sedge and other wetland plant species can play an important role in cleaning up contaminated wetland habitats and improving water quality.

Finally, Great Fen Sedge is a plant species that can inspire awe and wonder in those who observe it. The plant's tall, imposing stature, prickly leaves, and distinctive flowering spike make it a striking and memorable sight. Its ability to thrive in wetland habitats that are inhospitable to many other plant species also make it a symbol of resilience and adaptation in the face of adversity. In this way, Great Fen Sedge and other wetland plant species can serve as powerful reminders of the importance of conserving and protecting our natural world.

Distribution Map

Reproduced by kind permission of the BSBI.

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