Every state and territory in Australia, except for the Northern Territory, is experiencing the creeping march of the thorny invasive weed: African Boxthorn (Lycium ferocissimum). The weed can be a headache for coastal land owners and managers as it invades disturbed areas, pastures, adjacent waterways, coastal islands and sand dunes − and once it appears, it is very difficult to eradicate.
African Boxthorn characteristically grows in dense, thorny thickets, which led its original introduction from South Africa to Australia in the 1800’s as a hedge plant. In 2012 it was classed as a Weed of National Significance due to its impact on wildlife and pastoral animals, invasive characteristics and complex eradication issues.
Dr Mic Payne, the Northern Agricultural Catchments Council’s (NACC) Coastal and Marine Coordinator said, “Eradication methods involve a combination of physical removal and chemical application. However; because some native wildlife, such as mutton birds, will use the boxthorn as habitat absolute care must be taken when planning control works.” NACC has been involved in the fight against African Boxthorn in coastal areas of the Northern Agricultural Region.
Thickets were mechanically removed from alongside the Irwin River in Dongara and coastal dunes in Oakajee, north of Geraldton, in summer and autumn 2014. A Ditch-witch machine was utilised to physically pull up individual plants by the roots and was particularly beneficial in reducing damage to neighbouring native plants. Any roots still left in the ground were wiped with herbicide.
“The Ditch-witch equipment is ideal for treating light to moderate infestations of African Boxthorn, before using other follow-up techniques to treat regrowth. Both sites have been set up with photo- monitoring points which will be used to monitor regrowth of both African Boxthorn and native vegetation”, said Dr Payne.
Local community members attended NACC’s demonstration of boxthorn removal at Dongara in April 2014. This gave an opportunity for local land owners to speak with NACC and bush restoration experts for advice on removing the weed from their own properties.
NACC will continue to work with local communities in the NAR to combat this thorny invasion.