Invasive plants of Australian origin

There are a number of examples of Australian plants that have become invasive species when introduced into other countries.

Melaleucas in the Everglades

Perhaps the best known example of an Australian plant becoming an invasive species is the disastrous introduction of "Melaleuca quinquenervia" into Florida. As with all "Melaleuca" species, "M. quinquenervia" seeds prolifically. In the absence of natural predators, it spread throughout southern Florida; at one time it was estimated that 12% of southern Florida had been colonised by it. The colonised area included a substantial proportion of the Everglades, a revered national park and World Heritage Site. Attempts were made to control the spread by burning off, but this only exacerbated the problem as it encouraged seed dispersal while failing to kill the trees. The spread of "Melaleuca" is now managed by a combination of regular herbicide treatment and the introduction of an Australian beetle as a biological control.

"Acacia" in southern Africa

A number of "Acacia" species have become serious environmental pests after being introduced into southern Africa. The most troublesome species are "Acacia cyclops" and "Acacia saligna". Both are Western Australian coastal wattles, introduced to help bind drifting sand dunes. They remain serious pests, but some controls have been introduced. In the case of "Acacia saligna", the introduction of acacia seed weevils ("Melanterius" species) has achieved complete control. A lesser degree of control has been achieved for "Acacia cyclops" by the introduction of a gall rust fungus ("Uromycladium" species).

Other examples

* "Eucalyptus globulus" has spread rapidly since being introduced into California, reducing habitat for native species, and increasing the threat of wildfire.
* "Hakea sericea" has colonised much of the Table Mountain fynbos since its introduction into south Africa.
* "Cupaniopsis anacardioides", the tuckeroo, has become an invasive weed along the coastline of Florida. The plant there is known as carrotwood.

References

* [http://edis.ifas.ufl.edu/AG111 Discussion of C. anacardioides as a weed in Florida]