pest photo

John Wrigley, Australian National Botanic Gardens,
Ottelia; Duck-lettuce
Ottelia alismoides

Ottelia; Duck-lettuce (Ottelia alismoides) is an invasive plant of Tropical Asia and Australia. It was first detected in Louisiana in 1969.

This water weed can be invasive and form floating masses.
Summaries of State Plant Protection Laws and Regulations
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