Cabomba is a water plant and a weed of National Significance. Cabomba is an aquatic weed that grows quickly and produces vast amounts of submerged plant material. It was introduced into Australia from USA as an aquarium plant and first recorded in 1967. It is now posing a serious threat to waterways.

 

It is a perennial plant with branched stems that have white or reddish brown hairs growing on them. It has divided submerged leaves in the shape of a fan. These leaves secrete a sticky mucous which covers the submerged parts of the plant. The floating leaves, on the other hand, are small, diamond shaped and borne on the flowering branches. The flowers are solitary. They range in color from white to pale yellow and may also include a pink to purplish tinge.

 

Cabomba is sensitive to drying out and requires permanent shallow water, usually less than 3 m, but up to 10 m, deep.

 

Cabomba grows quickly and produces a large amount of plant material. The plant is fully submerged, except for occasional floating leaves and flowers above the water surface. The roots grow on the bottom of water bodies and the stems can reach the surface. Cabomba grows well on a silty bed but not so well on hard surfaces. It grows quickly, allowing it to respond to wide fluctuations in water depth.

 

The plant is used by aquarists as an ornamental and oxygenating plant for fish tanks. It is regarded as one of the worst weeds in Australia because of its invasiveness, potential for spread, and economic and environmental impacts. Weed control in aquatic environments is difficult and control options are limited by social and environmental pressures.

 

Did you know?

 

• Its use in the aquarium trade has led to some species being introduced to parts of the world, such as Australia, where they have become pestilential weeds.
• It can impede aquatic recreational activities and drowning is a risk for entangled swimmers.