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Common Marestail

Hippuris vulgaris

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:
Plantaginaceae (Plantain)
Life Cycle:
Maximum Size:
90 centimetres tall
Bogs, ditches, gardens, marshes, ponds, swamps, water, waterside.

Pink, no petals
The inconspicuous flowers of Marestail are minute and petalless. They are pink and form at the bases of the leaves.
A tiny, ovoid, green nut. Each nut contains 1 seed.
An unbranched, erect perennial waterweed which grows in still or slow flowing water. Most of the plant is submerged beneath the water. The strap-shaped leaves are in whorls of 6 to 12. Marestail has been semantically confused with Horsetails but they are two different plants altogether.
Other Names:
Bottlebrush, Cat-tail, Horse Tail, Joint Weed, Paddock Piper, Witch's Milk.
Frequency (UK):
Occasionally seen  

Similar Species

Other Information


Hippuris vulgaris, also known as mare's tail or horse tail, is a perennial aquatic plant that is native to Europe, Asia and North America. It typically grows in shallow water or muddy areas, and can reach heights of up to 3 feet. The plant has dark green, stiff, and hollow stems and the leaves are reduced to small sheaths that tightly wrap around the stem. The plant reproduces through spores and it's known for its thick roots that can help to prevent erosion of the banks. This plant is often used as an ornamental plant in water gardens and as a treatment for skin conditions. However, it is considered as a invasive species in some parts of the world and can outcompete native species for resources.


Common Marestail, also known as Hippuris vulgaris, is a unique aquatic plant species found in many parts of the world, including Europe, Asia, and North America. It is a fascinating plant that has adapted to life in water, and it has many interesting features that make it stand out from other aquatic plants.

Appearance and Habitat

The Common Marestail is a submerged plant that can grow up to 50cm in length. It has a thin stem that is green or brown in color and has small, narrow, and pointed leaves that are arranged in whorls around the stem. The leaves are around 1-2 cm long and have a smooth texture.

This plant is commonly found in freshwater habitats, including rivers, streams, ponds, and lakes. It grows in shallow water, usually less than 1 meter deep, and can be found in both still and flowing waters. It can also grow in brackish water and is known to tolerate a wide range of water conditions, including fluctuating water levels, high nutrient levels, and low oxygen levels.

Ecological Importance

The Common Marestail is an important plant for aquatic ecosystems as it provides shelter and food for a variety of aquatic organisms. Its stems and leaves offer shelter for small fish, invertebrates, and amphibians, while its seeds are a food source for waterfowl and other birds.

This plant is also known to play an essential role in water purification. It has been found to absorb excess nutrients from the water, including phosphorus and nitrogen, which can cause eutrophication and harm aquatic ecosystems.

Furthermore, the Common Marestail has medicinal properties and has been used traditionally in herbal medicine to treat various ailments such as stomach ailments, liver disorders, and respiratory problems.

Control Measures

Despite its ecological importance, the Common Marestail can become invasive in some water bodies, especially in nutrient-rich environments. Its rapid growth and ability to reproduce through both seeds and vegetative propagation can lead to the formation of dense stands, which can outcompete native plant species, alter the water chemistry, and affect the overall health of the ecosystem.

To control the spread of the Common Marestail, several measures can be taken. These include physical removal, such as hand-pulling or using cutting tools, as well as the use of herbicides. However, the use of herbicides should be carefully managed, as it can also harm non-target species and affect water quality.


In conclusion, the Common Marestail, Hippuris vulgaris, is a fascinating aquatic plant that plays an essential role in freshwater ecosystems. Its ability to provide shelter and food for aquatic organisms, purify water, and its medicinal properties make it a valuable species. However, its potential to become invasive in some water bodies highlights the need for proper management and control measures to ensure its long-term ecological sustainability.

More Information

The Common Marestail has several unique adaptations that have allowed it to thrive in aquatic environments. For example, it has a specialized root system that can anchor the plant to the substrate while also absorbing nutrients and oxygen from the water. Additionally, the plant has a unique ability to photosynthesize in low light conditions, which is important for its survival in deeper waters.

One interesting feature of the Common Marestail is its reproductive strategy. It can reproduce both sexually, through the production of seeds, and asexually, through vegetative propagation. This allows the plant to rapidly colonize new areas and establish dense stands, which can be beneficial or detrimental depending on the context.

The medicinal properties of the Common Marestail have been studied extensively, and several active compounds have been identified, including saponins, flavonoids, and tannins. These compounds have been shown to have anti-inflammatory, antimicrobial, and antioxidant properties, among other potential health benefits.

In addition to its ecological and medicinal value, the Common Marestail also has cultural significance. In some regions, it is used in traditional ceremonies and as a symbol of resilience and adaptability.

The Common Marestail is a fascinating and important plant species that deserves attention and protection. Its ability to adapt to changing environments, provide valuable ecosystem services, and offer potential health benefits make it a valuable resource for both humans and the natural world.

The Common Marestail has also been the subject of research in the field of phytoremediation, which is the use of plants to remove pollutants from soil and water. It has been found to be effective in removing heavy metals and organic pollutants from contaminated water, making it a promising candidate for use in environmental cleanup efforts.

Furthermore, the Common Marestail is often used in aquariums and water gardens due to its unique appearance and easy care requirements. Its thin, delicate leaves and intricate branching patterns make it a popular choice for aquascaping and adding visual interest to aquatic environments.

In terms of conservation, the Common Marestail is not currently listed as endangered or threatened, but its populations can be affected by habitat loss, water pollution, and other environmental factors. Efforts to protect and preserve the species and its habitats are important to ensure its continued survival and contribution to ecosystem health.

One of the challenges associated with managing the Common Marestail is its ability to develop resistance to herbicides. This resistance can occur through genetic mutations, natural selection, or a combination of both. The development of herbicide-resistant populations can make control measures less effective and more expensive, highlighting the importance of integrated management approaches that incorporate a variety of control methods.

Additionally, the Common Marestail is a good indicator of water quality, as its presence or absence can be used to assess the health of aquatic ecosystems. In areas where the plant is absent, it may indicate poor water quality or other environmental stressors. Monitoring the distribution and abundance of the Common Marestail can help inform management decisions and guide conservation efforts.

In terms of its traditional medicinal uses, the Common Marestail has been used for centuries in various cultures around the world. While some of its medicinal properties have been validated through scientific research, more studies are needed to fully understand the potential health benefits and risks associated with its use.

Overall, the Common Marestail is a fascinating and important plant species with a wide range of ecological, cultural, and medicinal significance. Efforts to understand its adaptations, properties, and roles in aquatic ecosystems can help inform management decisions and conservation efforts aimed at protecting this valuable resource.

Distribution Map

Reproduced by kind permission of the BSBI.

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