Karroo thorn, Vachellia (Acacia) karroo (Hayne) Banfi and Galasso, a thorny tree from Africa, was declared a State prohibited weed in Victoria under the Catchment and Land Protection Act 1994 in May 2003. State prohibited weeds are to be targeted with eradication from Victoria by the Department of Economic Development, Jobs, Transport and Resources (DEDJTR).In Victoria, Karoo thorn has only been detected as a very rarely planted tree in botanic gardens, zoos, parks, and a few other situations. The species has not been recorded as naturalised in Victoria, nor has it been recorded as being traded in the state. With nearly all known sites considered eradicated in recent years by DEDJTR, there are now only two known infested sites left in Victoria, and each of these has a ‘monitoring-only’ status. Further, no new sites have been detected in Victoria since 2004, despite this species having been targeted for detection by the Weed Spotters network for the last 10 years. The two remaining ‘monitoring-only’ sites are likely to be progressively deemed eradicated as their ‘monitoring-only’ period ends over the next few years. In Victoria, this species shows a very promising trend towards eradication, a target that is considered easier to achieve in this case than with many other weeds due to the favourable characteristics of the species and the nature of its incursion.
Hansford, M. (2015) Karoo thorn, Vachellia (Acacia) karroo: A State prohibited weed close to eradication. Plant Protection Quarterly 30(2), 51-58.