Curly water-thyme Lagarosiphon major, a waterweed native to South Africa, is now present in many ponds and lakes throughout New Zealand where it is considered invasive. Since becoming established in Lake Wanaka (New Zealand's fourth largest lake) 30 years ago, its accelerated spread around the lake has become the cause of concern both for amenity value (the lake is a popular tourist destination), and native flora and fauna alike.
It's invasive in New Zealand, the US, and Europe.
