Early detection of emerging invasive alien, Triplaris americana in Kwazulu-Natal, South Africa.

The Ant Tree (Triplaris americana) originates from South America, and was first taken to South Africa in the 1970s as an horticultural accent plant. This attractive species has become a popular garden ornamental, but is now considered an emerging Invasive Alien Plant (IAP) in KwaZulu-Natal, South Africa. It produces masses of winddispersed seeds that pose a threat to South Africa’s rich biodiversity. In South Africa T. americana is a declared invader and must be removed from private property.The Early Detection and Rapid Response programme (EDRR), which is sponsored by the South African Department of Environment has worked in collaboration with the private sector, non-government organisations and governmental institutions to detect and reduce the spread of T. americana in KwaZulu-Natal (KZN), resulting in significant progress towards the eradication of this species from KZN. Ecology of Triplaris Americana Triplaris americana (Polygononaceae) is a popular exotic ornamental tree in KZN, South Africa. Characterized by a smooth, greyish coloured bark, these trees often reach heights of up to 10 meters. This dioecious species produces bright pink flowers on female trees and inconspicuous flowers on male trees between April and September in South Africa. Seeds are enclosed in pinkish-brown 3winged wind-dispersed fruit. Each fruit encloses a single seed and on germination results in an individual seedling. T. americana is commonly called the Ant Tree, because of the ants which reside in the bark, flowers and leaves of this species. At least five Pseudomyrmex species.of ants are found to be associated with the Triplaris genus. Invasive potential and risk to South African biodiversity T. americana originates from South America and it is believed that the first Ant Tree introduced to South Africa in the 1970’s was for ornamental purposes. The attractive pink female flowers have led to the popularity of Ant Trees in gardening and landscaping in KZN. However, because of the efficient wind-dispersal of the thousands of 1 KZN Co-ordinator, Early Detection and Rapid Response Programme, South African National Biodiversity Institute, Durban, KwaZulu-Natal (KZN), South Africa, 2 National Co-ordinator, Early Detection and Rapid Response Programme, South African National Biodiversity Institute, Western Cape, South Africa Corresponding author’s email: r.lalla@sanbi.org.za Reshnee Lalla et al., Early detection of emerging... 794 three-winged fruit, masses of seedlings are produced. It is these offending seedlings that are the major cause for concern as they are capable of jumping the garden fence and spreading along roadsides and water courses, and negatively affecting natural systems. T. americana is a potential transformer and a declared weed under the South African Conservation of Agricultural Resources Act (CARA; 1983). EDRR efforts to reduce the spread of this species in South Africa The EDRR programme, which focuses on emerging IAPs, operates in a number of provinces of South Africa, including the east coast province of KwaZulu-Natal. Concerns about the invasiveness of T. americana, were first brought to the attention of the KZN unit of the EDRR programme in May 2009. An initial search on the South African Plant Invader Atlas (SAPIA), revealed only one record of T. americana in South Africa. Since then, the EDRR programme has embarked on an intensive search for plants in the area as well as various awarenessraising efforts to educate people about the negative effects of the Ant Tree. Figure 1. Adult Female Ant Tree, highlighting different plant features in the sub-set photos. EDRR efforts to reduce the spread of this species in KZN have aimed at altering the mindset of people from positive to negative associations with the tree. Although the escaped seedlings are the real Ants