European Water Chestnut

How to identify it

• Leaves are green, with sharply toothed edges and float on the service
• Leaves form a densely crowded rosette up to 30 cm in diameter
• Underwater leaves are feather-like with fine leaf segments
• Flowers are white, have four petals and are about 8 mm wide
• Produces a hard nut, 3-4 cm wide with sharp barbed spines
• Seeds that can reproduce are greenish brown and sink to the bottom
• Older seeds are black, floating, and cannot reproduce
• These are not the same as water chestnuts used in asian recipes!

Why it's bad

• Shades out other aquatic plants
• Very thick mats can cause problems with boating, canals and other recreation
• When it forms densely, it causes lots of decomposition, which reduces oxygen levels and can kill fish