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Black Bog-rush

Schoenus nigricans

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Plant Profile

Flowering Months:
Cyperaceae (Sedge)
Also in this family:
American Galingale, Birdsfoot Sedge, Black Alpine Sedge, 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, Great Fen 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:
60 centimetres tall
Bogs, fens, heathland, marshes, saltmarshes, sand dunes, wetland.

Brown, no petals
Small, dark brown, flattened spikelets.
An achene surrounded by a hard white coating.
Thread-like, unbranched, erect and grows in tight clumps straight out of the ground. The leaves have inrolled margins.
Other Names:
Black Bog Cotton, Black Sedge.
Frequency (UK):

Similar Species

Other Information


Schoenus nigricans, also known as black bog cotton or black-sedge, is a perennial flowering plant that is native to Africa. It is a member of the Cyperaceae family and is closely related to other members of the Schoenus genus, such as rust-colored bog cotton and brown bog cotton. The plant is known for its clusters of small, pink or purple flowers that are borne on slender, wiry stems above the foliage. It has narrow, green leaves and grows to be about 1-2 feet tall. S. nigricans is a popular garden plant and is often used in wetland or bog gardens. It is a hardy plant that is easy to grow and is tolerant of a wide range of soil types, but it prefers moist, well-drained soils and full sun to partial shade. The plant is attractive to pollinators and is a popular nectar source for bees, butterflies, and other insects. It is also used medicinally in some traditional cultures and has been used to treat a variety of ailments, including respiratory problems and skin irritation.


Black Bog-rush (Schoenus nigricans) is a species of rush that is native to various regions in the world including Europe, Asia, Africa, and Australia. This plant species is well known for its distinctive black appearance and its ability to grow in harsh environments such as bogs and fens.

One of the key features of the Black Bog-rush is its upright stem, which can reach up to 50 cm in height. The stem is covered with tiny, black, scale-like leaves, giving it its distinctive appearance. The plant produces spikes of small, inconspicuous flowers in the summer, which are followed by seeds that are dispersed by the wind.

In terms of habitat, the Black Bog-rush is well adapted to grow in wet environments. It is often found in bogs and fens, as well as in areas that are prone to flooding. This plant is also highly tolerant of acidic soils and can grow in soil with a pH as low as 4.5.

Despite its ability to grow in harsh environments, the Black Bog-rush is considered a rare plant species in many regions. This is due to the destruction of its natural habitats, as well as the impact of human activities such as agriculture, urbanization, and water management practices.

However, efforts are underway to conserve the Black Bog-rush and its habitats. In Europe, for example, the species is protected under the European Habitats Directive and is listed as a priority species in the United Kingdom's Biodiversity Action Plan.

In addition to its ornamental value, the Black Bog-rush is also of ecological significance. This plant provides a vital habitat for various species of insects, birds, and small mammals. The spikes of flowers attract pollinators such as bees, butterflies, and moths, and the seeds provide food for birds such as finches and sparrows. Additionally, the plant provides shelter and nesting sites for small mammals such as voles and shrews.

The Black Bog-rush is also important for the functioning of wetlands. It helps to prevent soil erosion and nutrient leaching, and it plays a role in water purification by removing pollutants and excess nutrients from the water. Furthermore, the plant helps to maintain the hydrology of wetlands by slowing down the flow of water and preventing flooding.

In terms of traditional uses, the Black Bog-rush has been used for a variety of purposes by different cultures throughout history. In Europe, the plant was traditionally used as a source of food and medicine. The seeds were roasted and used as a coffee substitute, and the leaves were used to treat a variety of ailments such as skin irritation, wounds, and colds.

Apart from its traditional uses, the Black Bog-rush has also been studied for its potential in phytoremediation. Phytoremediation is a process that uses plants to clean up contaminated soils and water. Studies have shown that the Black Bog-rush has the ability to absorb and accumulate heavy metals, such as lead and cadmium, from contaminated soils. This makes it a promising candidate for the remediation of contaminated sites, especially in wetlands where other remediation methods may not be feasible.

Another area of research for the Black Bog-rush is its potential for use as a biofuel. The plant's ability to grow in wet and acidic environments makes it an ideal candidate for the production of bioenergy. The stems of the plant contain a high amount of cellulose, which can be converted into biofuels such as ethanol and biogas. This makes the Black Bog-rush a promising alternative to traditional energy sources and a valuable resource for sustainable energy production.

In conclusion, the Black Bog-rush is a species with a wide range of ecological and economic values. Its ornamental value, importance for wildlife, and potential for phytoremediation and bioenergy production make it an important species to study and protect. Conservation efforts, such as habitat restoration and the introduction of protection measures, are essential to ensure the survival of this species and its continued contributions to the environment and society.


Black Bog-rush filmed at Gait Barrows National Nature Reserve in Lancashire on the 28th April 2023.


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Distribution Map

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