Sagittaria: declared pest

Page last updated: Monday, 20 July 2020 - 3:16pm

Please note: This content may be out of date and is currently under review.

Sagittaria (Sagittaria platyphylla) is a declared pest in Western Australia (WA). This article describes the nature of the plant with links to requirements land owners/occupiers must adhere to and pest control methods.

Form: aquatic — perennial

Status: present in WA

Sagittaria is an aquatic rhizomatous perennial to 80 centimetres tall, introduced from America. It is a Weed of National Significance (WoNS)


Stems: Triangular in cross section to 50 centimetres long.

Leaves: Emergent leaves to 25 centimetres long. Submerged leaves strap shaped to 50 centimetres long.

Flowers: On a leafless stem, arising in whorls more than two from the same position. Upper whorls are male flowers the lower females. There are three white petals.

Agricultural and economic impact

Mostly a water weed, a weed of irrigation channels and paddy rice. It is an important weed of rice crops and wetlands in the Eastern States, and is a threat to waterways and wetlands across WA, especially to the Ord River Irrigation Area. It has been found in the Canning River and at Albany.

Declared pest category

The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA). Search for sagittaria in the WAOL using the scientific name Sagittaria platyphylla.

Requirements for land owners/occupiers and other persons

Requirements for land owners/occupiers and other persons if this pest is found can be sourced through the declared plant requirements link.

Search > detect > report

MyPestGuide™ Reporter
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(Select 'Send report to MyWeedWatcher' from menu)

Pest and Disease Information Service (PaDIS)
+61 (0)8 9368 3080

Control method

Control methods for this declared plant can be found through the sagittaria control link.

Contact information

Pest and Disease Information Service (PaDIS)
+61 (0)8 9368 3080
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