Minute dioecious flowers but all reproduction is vegetative as only female plants occur in Ireland and Britain. Similar to Canadian Pondweed but leaves narrower, longer, more acute, often twisted. Usually in whorls of 4. Fresh root-tips white to grey-green. Stems to 3m. Identified by Paul Green
Still or slow-moving shallow or deep water. Rapid coloniser of new habitats.
First Irish record was at Lough Neagh 1984, now designated as a significant invasive plant in Ireland: Target 10 - Managing Invasive Alien species
Nuttall's Waterweed. The Gearagh, County Cork. August 2008