Water Soldier

Species: Stratiotes aloides

weed identification

common name
Water Soldier, Water Aloe, Pineapple Plant

Water soldier has an unusual growth habit. It is a submerged plant except in summer when it rises to the water surface to flower. The new leaves that grow in spring contain air pockets allowing the plant to float. As the older leaves die back in autumn they become waterlogged which causes the plant to sink again.

Water soldier can remain submerged all year round and can grow in depths of up to 5 m.


Commonly found in shallow, stagnant water bodies such as ponds, lakes and dams.

Not yet naturalised in Australia, has the potential to become invasive
native or exotic?

It reproduces predominately vegetatively, fragments of the plant can take root elsewhere. They can also sexually reproduce through their seeds.


It has edible fruit that is readily eaten by mobile animals. Fragments, seeds and fruit can be carried downstream if it enters water.


The benefits for an Australian aquatic ecosystem are not yet known but they are a source of food and habitat in other countries.

What does Water Soldier look like?

Use these images below to help you decide whether you are dealing with Water Soldier.

Disadvantages of Water Soldier

 Dense infestations of Water Soldier can cause significant problems such as:

  • Obstruct flow of pumps and irrigation systems

  • Form a dense monoculture that can dominate the water body

  • Reduce food and habitat for fish

  • Have a toxic effect on plankton

  • Restrict recreational activities such as boating

  • Reduce the aesthetic appeal


AQ200 Aquatic Herbicide – Chemical Herbicide designed to kill submerged weeds quickly. Use on mild to severe infestations.

Aquatic Weed Rake and Razor combo – DIY physical removal. Ideal for mild infestations, sensitive water bodies or to aid herbicide treatment

Aquatic Harvesting (Mobitrac) – Large amphibious machine that clears submerged aquatic weeds. Book this service for severe infestations or for larger water bodies.

prevention options

Aquatic Blue – Blue dye that may reduce temperature of the water body by reducing UV light penetration. This may then increase oxygen saturation.

Aerating Fountains – Reduces the severity and likelihood of aquatic weed infestations. Use in any body of water.