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Sea Fern Grass

Catapodium marinum

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Plant Profile

Flowering Months:
Poaceae (Grass)
Also in this family:
Alpine Catstail, Alpine Foxtail, Alpine Meadow-grass, Annual Beard-grass, Annual Meadow-grass, Arrow Bamboo, Barren Brome Grass, Bearded Couch Grass, Bearded Fescue, Bermuda Grass, Black Bent, Black Grass, Blue Fescue, Blue Moor-grass, Bog Hair-grass, Borrer's Saltmarsh Grass, Bread Wheat, Bristle Bent, Brown Bent, Brown Sedge, Bulbous Foxtail, Bulbous Meadow-grass, California Brome Grass, Canary Grass, Carnation Sedge, Cocksfoot, Cockspur, Common Bent, Common Cord-grass, Common Millet, Common Reed, Common Saltmarsh Grass, Compact Brome Grass, Corn, Couch Grass, Creeping Bent, Creeping Soft-grass, Crested Dog's-tail, Crested Hair-grass, Cultivated Oat, Curved Hard Grass, Cut Grass, Dense Silky Bent, Downy Oat-grass, Drooping Brome Grass, Drooping Tor Grass, Dune Fescue, Early Hair-grass, Early Meadow-grass, Early Sand-grass, False Brome Grass, False Oat-grass, Fern Grass, Fine-leaved Sheep's Fescue, Flattened Meadow-grass, Floating Sweet-grass, Foxtail Barley, French Oat, Giant Fescue, Glaucous Meadow-grass, Great Brome Grass, Greater Quaking Grass, Grey Hair-grass, Hairy Brome Grass, Hairy Finger-grass, Hard Fescue, Hard Grass, Harestail Grass, Heath Grass, Holy Grass, Hybrid Marram Grass, Italian Rye Grass, Knotroot Bristlegrass, Lesser Hairy Brome Grass, Lesser Quaking Grass, Loose Silky Bent, Lyme Grass, Marram Grass, Marsh Foxtail, Mat Grass, Mat-grass Fescue, Meadow Barley, Meadow Fescue, Meadow Foxtail, Meadow Oat-grass, Mountain Melick, Narrow-leaved Meadow-grass, Narrow-leaved Small-reed, Neglected Couch Grass, Nit Grass, Orange Foxtail, Pampas Grass, Perennial Rye Grass, Plicate Sweet-grass, Purple Moor-grass, Purple Small-reed, Purple-stem Catstail, Quaking Grass, Ratstail Fescue, Red Fescue, Reed Canary Grass, Reed Sweet-grass, Reflexed Saltmarsh Grass, Rescue Grass, Rough Meadow-grass, Rush-leaved Fescue, Sand Catstail, Sand Couch Grass, Scandinavian Small-reed, Scottish Small-reed, Sea Barley, Sea Couch Grass, Sheep's Fescue, Silver Hair-grass, Six-rowed Barley, Slender Brome Grass, Small Cord-grass, Small Sweet-grass, Smaller Catstail, Smooth Brome Grass, Smooth Cord-grass, Smooth Finger-grass, Smooth Meadow-grass, Soft Brome Grass, Somerset Hair-grass, Sorghum, Spreading Meadow-grass, Squirreltail Fescue, Stiff Brome Grass, Stiff Saltmarsh Grass, Sweet Vernal Grass, Tall Fescue, Timothy Grass, Tor Grass, Tufted Hair-grass, Two-rowed Barley, Upright Brome Grass, Velvet Bent, Viviparous Fescue, Wall Barley, Wavy Hair-grass, Wavy Meadow-grass, Whorl Grass, Wild Oat, Wood Barley, Wood Fescue, Wood Meadow-grass, Wood Melick, Wood Millet, Yellow Oat-grass, Yorkshire Fog
Life Cycle:
Maximum Size:
40 centimetres tall
Grassland, roadsides, rocky places, saltmarshes, sand dunes, sea cliffs, seaside, walls, wasteland.

Green, no petals
A one-sided flower spike which has between 5 and 10 stalkless (or almost stalkless) flowers. The flowers of Sea Fern Grass are similar to those of Fern Grass (Catapodium rigidum) but Sea Fern Grass has a more compact flower spike which never spreads.
The fruit is a dry, one-seeded caryopsis.
An annual grass found at the seaside and sometimes on salted road verges. Short, narrow, flat leaves. Sea Fern Grass is a stiff-looking plant with hairless, wiry stems. The leaves are similar to those of Fern Grass but the leaves of Sea Fern Grass are greener and more fleshy.
Other Names:
Sea Catapodium.
Frequency (UK):
Occasionally seen  

Similar Species

Other Information


Catapodium marinum, also known as sea catapodium, is a species of perennial grass in the genus Catapodium. It is native to Europe, Asia, and North America and is commonly found in coastal and sub-coastal habitats such as salt marshes, sandy beaches, and dunes. It forms dense clumps of narrow, green leaves and can grow to a height of up to 0.2 to 0.4 meters tall. The plant produces spikes of small, greenish-brown flowers in the summer.

Sea Catapodium is well adapted to grow in salt-rich soils, it can colonize and stabilize sandy and saline soils, making it a valuable plant for coastal habitat restoration, it can provide valuable habitat for wildlife and plants. It's also suitable for landscaping, and ornamental horticulture, particularly in coastal regions where it can provide a unique and attractive groundcover. However, it should be managed carefully, as it can become invasive in some regions and outcompete native plants, especially in habitats where it is not native.


Sea Fern Grass, scientifically known as Catapodium marinum, is a species of perennial grass that is commonly found along the coastlines of the Atlantic and Pacific oceans. This grass has long, thin leaves that resemble the fronds of a fern, which is why it is commonly referred to as Sea Fern Grass.

Sea Fern Grass is a hardy plant that can thrive in a variety of soil conditions, from sandy beaches to rocky shores. It is also known to be very salt-tolerant, which allows it to grow in areas where other plants cannot survive. This makes it an important species for stabilizing coastal ecosystems, as it helps to prevent erosion and protects against storm surges.

In addition to its ecological importance, Sea Fern Grass also has some interesting medicinal properties. The plant contains a number of compounds that have been found to have anti-inflammatory and antioxidant effects. This makes it useful in treating a variety of conditions, including arthritis, asthma, and skin disorders.

Sea Fern Grass has a long history of use in traditional medicine. In some cultures, it is believed to have magical properties and is used in rituals to ward off evil spirits. In others, it is used to treat a variety of ailments, including fever, stomach problems, and infections.

Despite its many benefits, Sea Fern Grass is not without its challenges. Like many coastal ecosystems, it is threatened by habitat destruction, pollution, and climate change. Rising sea levels and increased storm activity are putting pressure on coastal ecosystems, and Sea Fern Grass is particularly vulnerable to these threats.

Fortunately, efforts are underway to protect and restore coastal ecosystems around the world, including those that are home to Sea Fern Grass. In some areas, efforts are being made to reduce pollution and limit development along the coast. In others, scientists are working to develop new techniques for restoring degraded ecosystems and protecting vulnerable species like Sea Fern Grass.

Sea Fern Grass, Catapodium marinum, belongs to the Poaceae family, which is the fourth largest family of flowering plants. It is also known by other common names such as Saltmarsh Grass and Seaside Grass. The plant has a rhizomatous growth habit, meaning that it spreads by underground stems, which allows it to form dense stands and stabilize soil in coastal areas.

Sea Fern Grass is a valuable source of food for a variety of coastal animals, including waterfowl, shorebirds, and small mammals. The grass is also used as a nesting material by birds, and provides shelter and habitat for a variety of invertebrates and fish species.

In addition to its ecological and medicinal uses, Sea Fern Grass has also been used for a variety of other purposes. Historically, the plant was used to make baskets and mats, as well as to thatch roofs and cover walls. In some cultures, the grass was also used to make ropes and cords.

Sea Fern Grass is a fascinating plant with a rich history and many uses. As we continue to study and learn more about this important species, we can work to protect and preserve it for future generations. By working together to protect our coastal ecosystems, we can ensure that Sea Fern Grass and other important coastal species continue to thrive for years to come.

One interesting aspect of Sea Fern Grass is its unique photosynthetic pathway. Most plants use the C3 pathway for photosynthesis, which is a relatively inefficient process in terms of water use. However, Sea Fern Grass has evolved a specialized C4 pathway that allows it to photosynthesize more efficiently in environments with limited water availability, such as coastal ecosystems.

The C4 pathway allows Sea Fern Grass to conserve water by keeping its stomata, which are small pores on the leaves that allow for gas exchange, closed during the hottest part of the day. This helps to reduce water loss through transpiration, which is the process by which water evaporates from the leaves.

In addition to its ecological and medicinal uses, Sea Fern Grass has also been the subject of research in the fields of biofuels and bioremediation. Some researchers are exploring the possibility of using the plant as a source of biofuel, as its high biomass and ability to grow in marginal soils make it an attractive candidate for sustainable energy production.

Others are investigating the potential of Sea Fern Grass for bioremediation, which is the process of using living organisms to remove or neutralize pollutants from the environment. The plant has been found to be effective at removing heavy metals from contaminated soils, making it a promising tool for restoring degraded coastal ecosystems.

Overall, Sea Fern Grass is a versatile and fascinating plant with a wide range of uses and benefits. As we continue to explore and learn more about this important species, we can work to protect and preserve it for future generations to enjoy and benefit from.

Distribution Map

Reproduced by kind permission of the BSBI.

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