After our posting on this subject in February, Mexican Poppy’s have again reared their ugly heads in Alice Springs, this time in Laura Creek, south of Pine Gap. After rain at the beginning of April, germinating poppies were located by Land for Wildlife member Rod Cramer.
The Mexican Poppy (Argemone ochroleuca) is a native of Mexico and Central America. It was first recorded in Australia in 1845. A declared Class B weed in the Northern Territory, it mainly occurs in sandy river and creek beds, but has also been found in other disturbed sites in and around Alice Springs and the McDonnell Ranges.
The poppy’s only grow from seed, most of which falls at the base of the parent plant when ripe. It is easily spread downstream during floods but can be spread to other catchments, gardens and properties through the transportation of contaminated river sand. Infestations of the weed in remote areas such as along the Finke River probably result from the spread of sand and seed, inadvertently transported from infected areas on vehicles, people and camping equipment.
Small infestations of Mexican Poppy are easily controlled by hand pulling the plants. It is important to remove plants before they seed. The plants are an annual species that germinate after sufficient rain and seeds can remain viable in the soil for up to seven years. Control therefore needs to be repeated until the seed bank is depleted.
If your property is free of Mexican Poppy, you can help keep it that way by not using river sand from known infected areas (such as the Todd River) when landscaping or during other remediation work. Use sand from another area, or sand that has been treated to remove unwanted biological contaminants.
The Northern Territory Government has excellent information on this and other weeds on their website: www.nt.gov.au/nreta/weeds If you notice outbreaks of this weed or any other weed or plant you can’t identify that seems unusual, let us know about it. New weeds are appearing all the time and you can help stop their spread by letting the right people know.