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Glaucous Sedge

Carex flacca

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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, 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:
70 centimetres tall
Bogs, fens, gardens, grassland, marshes, riverbanks, riversides, waterside, wetland.

Brown, no petals
Upper purple-brown 4cm long spike (catkin) and 2 to 3 male catkins lower down.
Densely pack in the spike, round, up to 2mm across.
Grass-like. Leaf blade can be smooth and hairless, or rough to the touch.
Other Names:
Blue Green Sedge, Blue Sedge, Carnation-grass, Flabby Sedge, Glaucous Sedge, Gray Carex.
Frequency (UK):

Similar Species

Other Information


Carex flacca, also known as Glaucous Sedge or Blue Sedge, is a species of sedge that is native to Europe, Asia, and North Africa. It is a perennial herb that typically grows in wetland habitats such as marshes, bogs, and along the edges of streams and rivers. The plant has long, narrow leaves and small, inconspicuous brownish or greenish flowers that grow in spikes, the leaves of the plant are typically blue-green, giving the plant a glaucous appearance. It is often used as an ornamental plant in gardens and is also sometimes grown for its medicinal properties. It is considered as a common species in many areas, however, it is considered of conservation concern in some regions.


Glaucous Sedge, also known by its scientific name Carex flacca, is a perennial plant species belonging to the family Cyperaceae. This plant species is widespread in Europe, Asia, and North Africa, and is commonly found in damp and shady areas, including forests, wetlands, and meadows.

The Glaucous Sedge plant typically grows up to a height of 40-70cm, with a clump-forming habit. The leaves of the plant are narrow and long, with a blue-green glaucous hue, which gives the plant its name. The flowers are borne on spikelets, which are arranged in dense clusters or spikes. The spikelets are usually green or brown, and the flowers are wind-pollinated.

One of the most significant features of the Glaucous Sedge plant is its adaptability to different soil types, ranging from dry to moist soil, and from acidic to alkaline soils. The plant is also tolerant of shade and can grow well in areas with low light intensity. Due to these features, the Glaucous Sedge plant is an essential component of many natural habitats and ecosystems.

The Glaucous Sedge plant has several ecological and economic benefits. It provides food and shelter for a variety of wildlife species, including birds, insects, and small mammals. The plant's roots and leaves also help stabilize soil and prevent erosion, especially in wetland areas. Additionally, the plant is a source of traditional medicines and is used to treat a wide range of health conditions, including stomach ailments, headaches, and fever.

However, like many other plant species, the Glaucous Sedge plant is facing several threats, including habitat loss and degradation due to human activities, climate change, and invasive species. Conservation efforts are essential to protect this plant species and its habitats from further decline.

The Glaucous Sedge plant is an essential component of many ecosystems, providing a range of ecological and economic benefits. Its adaptability to different soil types and tolerance to shade make it a valuable species, especially in wetland areas. However, its decline due to human activities and other threats calls for urgent conservation efforts to protect it and its habitats for future generations.

The Glaucous Sedge plant has also been used for a variety of human purposes, including basket weaving, thatching, and making ropes and cords. Its long, narrow leaves are strong and flexible, making them ideal for weaving into baskets and other handicrafts. The plant's tough stems and leaves can also be used to make ropes and cords, while its dried leaves can be used as thatching material for roofs.

In addition to its traditional uses, the Glaucous Sedge plant is also being studied for its potential in phytoremediation. Phytoremediation is the use of plants to remove pollutants and contaminants from the soil or water. The Glaucous Sedge plant has been found to be effective in removing heavy metals and other pollutants from contaminated soil and water, making it a potentially valuable tool for environmental restoration and remediation.

Despite its many benefits, the Glaucous Sedge plant is facing threats from a variety of sources, including habitat loss and degradation, climate change, and invasive species. Wetland areas, in particular, are at risk due to human activities such as drainage, development, and agriculture. As a result, conservation efforts are essential to protect this valuable plant species and its habitats.

Conservation efforts for the Glaucous Sedge plant may include the restoration and protection of wetland areas, the control of invasive species, and the promotion of sustainable land use practices. In addition, education and awareness-raising efforts may be needed to promote the value of this plant species and its role in ecosystem health and sustainability.

In conclusion, the Glaucous Sedge plant is a valuable and versatile plant species with a range of ecological, economic, and cultural benefits. However, its decline due to various threats highlights the urgent need for conservation efforts to protect this species and its habitats. By working together to promote the conservation of the Glaucous Sedge plant, we can help ensure its survival for future generations.


Glaucous Sedge filmed in Capernwray, Lancashire along the Lancaster Canal on the 28th April 2023.


Music credits
Constancy Part 1 - The Descent by Kevin MacLeod is licensed under a Creative Commons Attribution 4.0 license.

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Distribution Map

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