Australian swamp stonecrop (Crassula helmsii) - Non-native Species

Australian swamp stonecrop
(Photo credit: Keith Luxford)

Also known as New Zealand Pygmy Weed, this aquatic plant was introduced to Britain from Tasmania in 1911 and was first recorded in the wild in 1956. Crassula helmsii is an extremely invasive species which is not easy to control. It forms dense mats on water bodies that shade out other aquatic vegetation, consequently having a negative impact upon fish and invertebrate communities. Crassula can also increase the risk of flooding and restrict amenity activities, such as fishing.

Australian swamp stonecrop sheet
Management advice