1. PORT JACKSON – Acacia saligna
YOUNG PORT JACKSON – Acacia saligna (Photo by Steve Coe)
Category 2 plant.
A native of south-western Australia, the Port Jackson is a member of the Legume family, Fabaceae . It is an evergreen with a willowy appearance and has flattened, leathery, deep green, mainly drooping leaves, which are more upright and broader in the immature plants. It can grow into a tree, up to 9 meters tall and spreads prolifically, growing in dense thickets. It was originally deliberately imported and planted to stabilize sand dunes, but has now become a runaway menace.
PORT JACKSON SEEDLING – Acacia saligna (Photo by Steve Coe)
The Port Jackson does not have true leaves and what we are seeing in the photo above are actually leaf stems (Phyllodes). From August to October Port Jacksons comes into flower and are covered in masses of bright yellow, fluffy inflorescence, which are shortly followed by bean like seed pods. The seeds are spread by wind, flowing water and by the passage of vehicles and other human activity. Much of the invasion of new areas (and re-colonization after clearing) takes place along the verges of roads.
PORT JACKSON SHOWING INFLORESCENCE AND SEED PODS
(Photo from Plant Invaders (1978) – Botanical Research Institute Handbook)
The control of Port Jackson is not simple as the wretched plant coppices readily, after being cut down (or burnt), which results in an even greater proliferation of plant material. The plant and its roots must be removed entirely or an approved chemical herbicide must be painted onto the cut area. It has soft wood, not suited for firewood as it burns too fast.
GALLS ON PORT JACKSON FROM RUST FUNGUS (Photo by Steve Coe)
Many Port Jackson shrubs, such as the young plant in the photo above, are characterized by the appearance of hanging brown nodules or galls on their branches. These are the result of human intervention, where carefully researched biocontrol measures are used to deliberately infect a Port Jacksom population with rust fungus to destroy the vigor of these invasive alien in a particular area . This fungus is a specific parasite of the Port Jackson and are released amongst these alien shrubs, as an on-going biological control programme.
NOTE : IT IS AN OFFENSE TO HAVE THIS PLANT ON YOUR PROPERTY –
ERADICATE IT ON SIGHT.
Click on the specific plant below to see photo and description:
