The interaction among species can be influenced by neutral processes in which more abundant species have high effect on the structure of interaction or can be influenced by trait matching. Despite both variables (abundance and species traits) influencing the interaction of species in mutualistic networks few studies showed their importance in antagonistic networks. Here we posed the question: what are the main predictors of the liana–tree interactions: species abundance biological traits or both? In a savanna woodland fragment in south-eastern Brazil we sampled lianas and trees in 1 ha where we recorded the abundance maximum height and bark roughness of tree species as well as abundance maximum diameter and climbing system of liana species. For each species we calculated their contribution to nestedness (ni) which is a measure of network structure and performed simple linear regressions between ni and abundance and species traits. Abundant species contribute more to ni than rare species indicating that neutral processes affect interactions between lianas and trees probably because lianas are opportunistic and climb trees in their neighbourhood. The only trait related to ni was tree height which can indicate that light availability can have a considerable role on network structure between both growth forms. Therefore the importance of species abundance and tree height can be related to opportunism of lianas on climbing the most suitable tree in their neighbourhood.