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Curly Leaved Waterweed - Lagarosiphon Major

Marine; freshwater lakes, canals, low energy rivers and streams.

Currently not well established however Lough Corrib has a considerable infestation.

What does it look like?
The plants leaves are green and are strongly curved and composed of 3 or 4 stems in a spiral. The long stem is brittle and easily broken. Only female plants are present and all reproduction is by fragmentation or vegetative means.

Curly Leaved Waterweed clogs waterways and alters native ecosystems, impacting native water plants, insects and fish. It outcompetes native species and can grow in water up to 6 m deep.

Where is it originally from?
The Curly Leaved Waterweed originates from southern Africa but is now invasive in mainland Europe and Britain.

©2007 Department of the Environment, Heritage and Local Government