Story: Water quality

A handful of didymo

A handful of didymo

Didymosphenia geminata – known as didymo or ‘rock snot’ – causes serious damage to waterways. Although it looks slimy, it feels like wet cotton wool. First detected in New Zealand in 2004, it is native to the cool waters of northern North America and Europe.

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Ministry for Primary Industries, Biosecurity New Zealand

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How to cite this page:

Mike Scarsbrook and Kit Rutherford, 'Water quality - Problem plants and microbes', Te Ara - the Encyclopedia of New Zealand, (accessed 25 May 2022)

Story by Mike Scarsbrook and Kit Rutherford, published 24 Nov 2008, updated 18 Jul 2016