People are reminded to be vigilant when buying aquatic plants, after two of Australia’s worst water weeds were recently found for sale.

Department of Agriculture and Food research officer Sandy Lloyd said salvinia had been found for sale online, incorrectly named giant duckweed. 

Salvinia is a Weed of National Significance which can devastate waterways and severely impact on the environment, agriculture, and tourism.

“Salvinia is prohibited from being grown in Western Australia and the weeds for sale on this particular website and also at commercial premises in O’Connor have been confiscated,” Ms Lloyd said.

“It is one of Australia’s most damaging aquatic weeds, which can block waterways, pollute drinking water, and displace native plants and animals.”

Salvinia is a free-floating aquatic fern that has fronds in pairs along the stem, which are bright green and covered with short hairs. The plants can be up to 20cm long.

Ms Lloyd said water hyacinth was another serious weed which had been offered for sale recently at a weekend market in Melville. A woman who bought water hyacinth at the market later reported it to the department when a friend told her it was banned.   “Water hyacinth is one of the world’s worst weeds, choking up rivers, lakes and other waterways,” she said.  Both weeds are declared plants in WA, prohibited from sale and must be destroyed when found. Anyone with suspect aquatic weeds should not dump them in creeks or drains where they could proliferate and spread. They should be reported to the department’s Pest and Disease Information Service on 1800 084 881.