Lantana (Lantana camara) is a large flowering shrub native to Central and South America that readily grows into thickets. After being brought to Australia as an ornamental garden plant in about 1841, the weed quickly escaped domestic cultivation and within 20 years was established in the wild. Lantana was first declared noxious around 1920 and by the 1950s it had spread over more than 1600 kilometres of the eastern Australian coastline. In 2006, the invasion, establishment and spread of lantana was listed as a Key Threatening Process in Schedule 3 under the NSW Threatened Species Conservation Act 1995.
Lantana occurs in most coastal and eastern escarpment areas from Narooma to Far North Queensland. It thrives in warm environments with high rainfall where the weed grows along forest edges, penetrates disturbed rainforest and invades open eucalypt woodlands and pastures. Within Australia, it has invaded at least 4 million hectares.
Impact on the environment and agriculture
Lantana forms dense thickets that exclude native species, leading to its complete dominance of the understorey and eventually the canopy. It has also been estimated that graziers spend $17.1 million a year on lantana control and lose in excess of $104 million in production due to lantana invasion. It is spread mainly by birds. Lantana has been declared a noxious weed in NSW and is also listed as a Weed of National Significance. A recent review has assessed the declaration status of Lantana camara, and other species including Lantana montevidensis and ornamental lantana varieties in NSW.
Management by NPWS
The NSW National Parks and Wildlife Service (NPWS), now part of the Office of Environment and Heritage, uses an integrated approach to manage the weed, combining different control methods to achieve the best results and minimise its impact on native plant species. Many lantana control programs are run in conjunction with local communities and councils. When management is undertaken for biodiversity conservation, five-year site management plans are completed.
Herbicides are an important tool for managing lantana. Mechanical control methods include hand-pulling of seedlings, slashing, grubbing (digging out by the roots), felling and bulldozing. Biological control attempts to control weeds by introducing the weed's own natural enemies. A promising option for lantana is leaf rust, but research is also continuing into the biocontrol potential of a bud mite, and several pathogens and beetles.
Some NPWS lantana control programs
Cooperative cross-tenure control programs on the South Coast
NPWS is working with Eurobodalla Shire Council and the Tilba Landcare Group to coordinate control of lantana across all land tenures at Mt Dromaderry to both improve the productivity of agricultural lands and protect regionally significant plant communities and the Aboriginal heritage of Gulaga National Park.
Protecting rock-wallabies in Kangaroo Valley
In Kangaroo Valley in the Southern Highlands, NPWS has removed large areas of lantana to protect important habitat for brush-tailed rock-wallabies.
Protecting rainforest on the Hunter Coast
A NPWS weed control program on Snapper Island Nature Reserve has halved lantana infestations, allowing the regeneration of the island's endangered ecological community of littoral rainforest.
Lantana control in the Northern Tablelands
In the Nymboida National Park in the Glen Innes region, NPWS is controlling lantana infestations wherever they occur along approximately 25 km of the Mann River.
Biological control research
NPWS is a major contributor to a joint research program on biological control of lantana by Biosecurity Queensland and NSW Trade & Investment. A leaf rust (Prospodium tuberculatum) has now been released at over 100 sites in NSW stretching from Mt Warning to Central Tilba.