Alligator weed

Pest Plant Alligator Weed

Alligator weed (Alternanthera philoxeroides) is classified as a category 3 pest plant under Queensland's Biosecurity Act 2014. It is also identified in the Federal government's Weeds of National Significance register.

Alligator weed is a South American perennial plant that grows on land in damp soil or in water as dense floating mats. The species is identified by its:

  • hollow stems
  • dark green leaves arranged in opposite pairs along the stems
  • white paper-like, ball-shaped flowers, which appear around mid-summer.

If you find a plant in a waterway that resembles the characteristics of alligator weed, please click on the following button and scroll down to Pest plants to complete our online form. Alternatively, please contact us on 07 5667 5988.

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