Rangers Corner - Weed Management

23rd Nov 2011

Djunbunji Rangers to undertake weed control activities on country.

ACDC Training undertaken late last year has certified Djunbunji Rangers to undertake weed control activities on country. Working with our QPWS and QASSIT partners, Rangers have been slashing tracks on East Trinity Reserve to provide 4X4 access to isolated outcrops of Singapore daisy and guava. Our capacity to manage weeds has been vastly improved with the commissioning of our modern QUIKSPRAY unit.

Djunbunji Rangers have been actively managing pond apple on East Trinity Reserve. Pond Apple (Annona glabra) is an aggressive, semi-deciduous tree that has the ability to invade estuaries and mangrove ecosystems of tropical Australia that have previously been undisturbed natural habitats.

Introduced prior to 1886 and native to Central Americas, pond apple was used as a root stock for the custard apple tree. Its fruit is similar to a smooth skinned custard apple which can float on ocean currents for up to 1300 kilometres. Pond apple distribution is prominently wet tropics, Cape York Peninsula and northern island communities of Queensland with a small infestation identified at Mackay.

Pond apple?s ability to grow in flooded areas and to tolerate salt water has enabled it to spread through much of northern Queensland?s wet tropics area. It now infests more than 2000 ha of the Wet Tropics Bioregion, and threatens melaleuca wetlands and native mangrove communities. It is also spread by cassowaries and feral pigs.

Infestations on East Trinity Reserve are mapped and areas for control determined in consultation with QPWS and QASSIT. Stem injection is the preferred method for treating pond apple in aquatic habitats because it minimises herbicidal runoff and impacts on non-target plants and animals.

Control costs of pond apple are high due to the nature of the infestations and challenging work environments posing health and safety risks to control operators.

To learn more about this weed and how you can help, go to: guidelines/wons/pubs/a-glabra.pdf