Erica species are not found naturally in Australia, but have been distributed here widely as ornamental plants. Approximately 18 Erica species are recorded to have naturalised in Australia. One of these, besom heath (Erica scoparia L.), is only known from northern Tasmania where it was first formally recorded as naturalised in 1983. It is now threatening to become a state-wide weed.
Weed risk assessment (and experience) suggest that besom heath has invasive potential at least equal to its better known weedy relatives Spanish heath (Erica lusitanica Rudolphi) and tree heath (Erica arborea L.). The northern Tasmanian besom heath infestation now covers approximately 250 ha with approximately 20 outlier infestations (of less than 20 ha each).
Containment measures are in place for besom heath in Tasmania. However, ongoing spread is inevitable. Besom heath is a prolific producer of fine seed that spreads on vehicles and equipment, in soil and with other materials. With movement of people, vehicles and freight between Tasmania and Victoria on a daily basis, besom heath should be on mainland jurisdiction’s biosecurity ‘radars’ (particularly Victoria’s). Should it appear, rapid early efforts should be made to eradicate it.
Noble, M. and Smith, A. (2016). The invasive threat of besom heath (Erica scoparia) (in Tasmania) to Victoria. Plant Protection Quarterly 31(2), 55-58.