The routine inspection of a property in Narrabri Shire has resulted in the detection of the invasive weed frogbit.

Frogbit (Limnobium Laevigatum) is classed as a prohibited matter under the Biosecurity Act 2015.

Frogbit is a perennial fast-growing, floating, aquatic plant.

The noxious weed invades and smothers waterways, blocking irrigation channels, limiting recreational activities, and reducing light, food, and shelter for aquatic animals.

Additionally, it creates dangerous conditions by hiding the water surface and making it appear like firm ground.

It is illegal to buy, trade or sell frogbit.

Frogbit leaves are usually bright green, usually rounded at the tip, up to four-centimetres across and are glossy on top.

Young leaves are round, spongy on the underside and float lying flat on the water surface.

As the leaves mature they lose their spongy underside become more oval shaped and can extend up to 50 cm above the water.

Flowers are typically about 13 mm wide, white, greenish-white or yellowish and either male or female (male flowers are on longer stalks often above the female flowers).

Frogbit grows on the surface of freshwater rivers, ponds, dams, lakes, canals and other aquatic habitats.

It can grow in shade and full sun. It grows in a wide range of environments but prefers water that is 15–28°C with a pH of 6–8. It can tolerate slightly saline water.

Frogbit is native to Central and South America.

Narrabri Shire Council advised of the weed’s detection on Monday afternoon and has encouraged all residents across the shire to familiarise themselves with the identification of frogbit.

Do not attempt to treat or dispose of frogbit, the NSW Department of Primary Industries advises. People are asked to report any suspicious weeds to council as a priority.

Residents can use the Department of Primary Industries NSW WeedWise website additional information regarding frogbit.

For identification, to report possible sites or to find out further information, please contact council’s biosecurity officers on 02 6799 6866.

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