Water soldier, water-aloe

Stratiotes aloides -- Center for Aquatic and Invasive Plants

Water soldier is in the Hydrocharitaceae family. Water soldier is an invasive perennial aquatic plant that is native to Europe and northwest Asia. The only known wild population in North America was found in the Trent River in 2008, near the Hamlet of Trent River, Ontario, Canada. Water soldier is used as an ornamental plant in water gardens, the likely source of its introduction to the Trent River.

Water soldier is similar in appearance to an aloe plant, spider plant or the top of a pineapple. Water soldier may be confused with other aquatic plants in Ontario, such as native bur-reeds, arrowheads or eel-grass. However, none of these plants has serrated leaf edges, which can be used to easily distinguish water soldier from these other aquatic plants.

Other identifying features and characteristics of this plant include the following:

  • It is a submerged aquatic plant which becomes buoyant during the summer months. As the leaves mature, they become waterlogged and the plant sinks below the water’s surface.
  • Leaves are 40 cm long, sword-shaped, bright green, with sharp spines, and form a large rosette, or group of leaves arranged in a circle.
  • Flowering has not been observed in Ontario plants. However, if present, flowers are white with three petals, developing into 1 to 3.5 cm long fleshy berries – each containing up to 24 seeds.
  • Roots can be, but are not always, attached to the mud at the bottom.
  • Plants can be found growing in depths of up to 5 metres.
  • Mature water soldier plants produce offsets, which are similar to those produced by the household spider plant. Offsets look like smaller versions of the adult plant.

Source: Water Soldier (Stratiotes aloides), ontario.ca/invasivespecies