The March weed of the month is the Opuntia cactus group.
Commonly known as Prickly pears, these spiny critters and Weeds of National Significance are a diverse group of cacti that can cause enormous damage to ecosystems and agriculture across huge areas of Australia.
Not native - invasive!
Despite the successful introduction of the Cactoblastis moth on Common pear in the late 1920’s, many other varieties of Prickly pear persist. Australia has no native cacti, with all species coming from north, central and south America. Twenty-two distinct species are declared as invasive weeds in NSW alone.
Features of the Optunia cactus group
Can form large, spiny monocultures that greatly reduce agricultural productivity, trap and injure native wildlife, harbour invasive pests and reduce biodiversity over huge areas.
Typically covered in spines, with either large paddle-like cladodes (leaves) or long cylindrical stems.
Often produce large, vibrant flowers, with some capable of reproducing by seed but most spreading by broken plant parts.
Plant parts are easily spread by machinery driving through infested areas, with spines able to penetrate car tyres and be transported long distances.
Serious fines apply
Unfortunately the main method of spread is the ornamental plant trade. Cactus growers continue to sell plants online despite bans on trade. All Opuntia, Cylindropuntia and Austrocylindropuntia cacti (apart from the Indian fig, Opuntia ficus-indica) are regulated by a Mandatory Measures regulation, which states that they must not be imported, sold, bartered, exchanged or offered for sale. Fines of up to $220,000 are possible for anyone dealing with these plants.
Help with identification and control
If you need to control an infestation of Prickly pear or need help with identification please contact Port Macquarie Hastings Council’s biosecurity officer and refer to NSW WeedWise.
