Influence of Lantana camara and its removal on tree dynamics in a recently burnt wet Sclerophyll forest in Northern NSW

Abstract

Lantana (Lantana camara) has adverse effects on plant communities across Australia. Fire, sometimes recommended as a management strategy for Lantana, is likely to have both beneficial and detrimental effects on Lantana and native trees. It is therefore important to evaluate the regeneration of Lantana-invaded woody plant communities postfire. We examined the effect of Lantana removal by herbicide spray on both Lantana density and small tree (<5cm diameter at breast height; DBH) attributes (abundance, height, DBH and diversity) in an area previously burnt. On a subset of the data, which was not sprayed, we also examined small tree attributes along a gradient of Lantana density. The herbicide treatment of postfire Lantana regrowth significantly reduced Lantana density compared to the areas left unmanaged by herbicide and increased the stem diameter of Celery Wood (Polyscias elegans). We found that, as Lantana stem density increased in no-spray plots, the abundance of Poison Peach (Trema tomentosa), Celery Wood, and Eucalyptus and allied genera (Angophora and Corymbia) decreased. In addition, height of wattles (Acacia irrorata and A. maidenii) increased with increasing Lantana density. As postfire regeneration of Lantana reduced abundance of some species, additional control of Lantana was required to assist community regeneration.