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Esthwaite Waterweed

Hydrilla verticillata

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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Contents

Plant Profile

Flowering Months:
JAN  FEB  MAR  APR  MAY  JUN  JUL  AUG  SEP  OCT  NOV  DEC
Order:
Alismatales
Family:
Hydrocharitaceae (Naiad)
Type:
Flower
Life Cycle:
Perennial
Maximum Size:
7.5 metres long
Habitats:
Ponds, water, wetland.

Flower:
֍
White, 3 petals
 
Tiny and inconspicuous. The translucent, whitish-coloured flowers are seldom seen. Water pollinated.
Fruit:
Bud-like structures, known as turions. In fruit from June to October.
Leaves:
An annual or perennial aquatic plant with very narrow, finely toothed, pointed leaves and a sharp tip. The leaves are in whorls of 4 to 5. Grows in shallow and deep water. Similar in appearance to Canadian Waterweed (Elodea canadensis) but the leaves of that are in whorls of 3 and there are no teeth or spines.
Other Names:
Hydrilla, Water Thyme.
Frequency (UK):
Rarely seen  

Similar Species

Other Information

Summary

Hydrilla verticillata is a species of aquatic plant, usually treated as containing just one species. It has been observed in the Mojave and Colorado deserts, and is a prohibited plant according to the USDA Noxious Weed List and the Florida Prohibited Plant List. Hydrilla is mainly introduced to new waters as fragments on recreational boats, their motors and trailers and in live wells. Stem pieces root in the substrate, and it outcompetes native submerged aquatic vegetation and can quickly fill a pond or lake. Hydrilla has a CO2 compensation point that varies from high (above 50 microliters per liter) to low (10 to 25 microliters per liter).

Blog

Eskthwaite Waterweed: Understanding Hydrilla Verticillata

Eskthwaite waterweed, also known as Hydrilla verticillata, is a submerged aquatic plant that is native to Asia but has been introduced to several countries as an ornamental plant. This species of waterweed is highly invasive and can cause significant ecological damage to aquatic ecosystems. In this blog, we will explore the biology, ecology, and management of Eskthwaite waterweed.

Biology of Eskthwaite Waterweed

Hydrilla verticillata is a perennial plant that grows underwater and can reach up to 15 meters in length. The leaves of the plant are small, usually less than 2 cm in length, and are arranged in whorls around the stem. The plant produces tiny white or yellowish flowers, which are rarely seen as they grow below the water surface. Eskthwaite waterweed is a fast-growing plant and can quickly form dense mats of vegetation, which can smother other aquatic plants and wildlife.

Ecology of Eskthwaite Waterweed

Eskthwaite waterweed is a highly invasive species that can quickly establish itself in new aquatic environments. The plant is capable of reproducing from fragments, meaning that even a small piece of plant material can generate a new population. This, combined with the plant's fast growth, means that Eskthwaite waterweed can quickly spread and dominate aquatic ecosystems. The dense mats of vegetation created by the plant can also alter water chemistry and light conditions, making it difficult for other plants and wildlife to survive.

Management of Eskthwaite Waterweed

Eskthwaite waterweed is a challenging plant to manage as it is highly resilient and difficult to control. However, there are several management options available, including physical removal, chemical control, and biological control. Physical removal of the plant is the most effective method, but can be difficult and time-consuming. Chemical control involves the use of herbicides, but these can also have negative impacts on non-target species and water quality.

Biological control involves the use of natural enemies of the plant, such as herbivores or pathogens, to reduce the population of Eskthwaite waterweed. This method is considered the most sustainable and environmentally-friendly approach, but it may take several years for the population of Eskthwaite waterweed to be reduced to a manageable level.

In conclusion, Eskthwaite waterweed is a highly invasive species that can have significant impacts on aquatic ecosystems. It is important that we understand the biology, ecology, and management of this plant to ensure that we can effectively control its spread and minimize its negative impacts on the environment.

Impacts of Eskthwaite Waterweed on Ecosystems

Eskthwaite waterweed can have a wide range of negative impacts on aquatic ecosystems, including:

  1. Alteration of Water Chemistry: The dense mats of vegetation created by Eskthwaite waterweed can change the water chemistry, leading to an increase in nutrients and a decrease in dissolved oxygen. This can lead to the death of other aquatic plants and wildlife.

  2. Impacts on Biodiversity: Eskthwaite waterweed can quickly outcompete and smother other aquatic plants, reducing the biodiversity of the ecosystem. This can also impact the food chain, as many aquatic species rely on other plants for food and habitat.

  3. Impacts on Recreational Activities: Eskthwaite waterweed can have significant impacts on recreational activities, such as boating, fishing, and swimming. The dense mats of vegetation can make it difficult for boats to navigate, and the decrease in water quality can impact the health of fish populations, making fishing less productive.

  4. Economic Impacts: Eskthwaite waterweed can also have economic impacts, as it can reduce the value of property and decrease the recreational use of waterways. It can also increase the cost of water treatment, as the increased nutrients in the water can lead to more algae growth and require more treatment to meet water quality standards.

Prevention and Early Detection

Preventing the introduction and spread of Eskthwaite waterweed is essential to minimize its negative impacts on aquatic ecosystems. This can be achieved through a combination of measures, including:

  1. Education: Raising awareness of the risks associated with Eskthwaite waterweed and promoting best practices for avoiding its spread can help prevent its introduction.

  2. Regulations: Implementing regulations and restrictions on the importation, sale, and use of Eskthwaite waterweed can help prevent its spread.

  3. Early Detection: Monitoring for the presence of Eskthwaite waterweed and responding quickly to new outbreaks can help prevent its spread and minimize its impacts.

Eskthwaite waterweed is a highly invasive species that can have significant impacts on aquatic ecosystems. It is important that we understand the biology, ecology, and management of this plant to ensure that we can effectively control its spread and minimize its negative impacts on the environment. Through a combination of prevention and early detection measures, and effective management strategies, we can protect our aquatic ecosystems and preserve the biodiversity of our waterways.

Human Benefits of Eskthwaite Waterweed

Despite its negative impacts on aquatic ecosystems, Eskthwaite waterweed can also have some benefits for humans. These benefits include:

  1. Aquatic Agriculture: Eskthwaite waterweed can be used as a food source for aquatic animals, such as fish and waterfowl, which can then be harvested for human consumption.

  2. Ornamental Use: Eskthwaite waterweed can be used as an ornamental plant in aquaria and ponds. Its fast growth rate and ability to thrive in a wide range of conditions make it a popular choice for aquarium owners.

  3. Bioremediation: Eskthwaite waterweed has been shown to have the ability to remove pollutants, such as heavy metals, from water. This makes it a potentially useful tool for water treatment and bioremediation.

However, it is important to note that despite these benefits, the negative impacts of Eskthwaite waterweed on aquatic ecosystems far outweigh any benefits. Therefore, it is essential that measures are taken to prevent its spread and minimize its impacts on the environment.

Potential Future Research Directions

Further research on Eskthwaite waterweed can help improve our understanding of its biology, ecology, and management, and lead to more effective strategies for controlling its spread and minimizing its impacts. Some potential research directions include:

  1. Understanding its biology: Studying the growth, reproduction, and ecology of Eskthwaite waterweed can provide valuable information for its management and control.

  2. Evaluating management strategies: Investigating the effectiveness of different management strategies, such as physical removal, chemical control, and biological control, can help determine the most effective approach for controlling Eskthwaite waterweed.

  3. Improving bioremediation: Researching the ability of Eskthwaite waterweed to remove pollutants from water, and improving this ability, can help develop new tools for water treatment and bioremediation.

Conclusion

Eskthwaite waterweed is a highly invasive species that can have significant impacts on aquatic ecosystems. Further research on its biology, ecology, and management can help improve our understanding of this plant and lead to more effective strategies for controlling its spread and minimizing its impacts. By working together, we can protect our aquatic ecosystems and preserve the biodiversity of our waterways.


Distribution Map

Reproduced by kind permission of the BSBI.

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