The Arboretum was built in 1959 and occupies an area of 3.2 ha. As one of the earliest collections and an important gene pool of the botanical garden, the Arboretum is home to 750 tropical plant species. Its main function is to collect and reserve endangered and rare plants, important commercial and economic trees, such as Ylang Ylang (Cananga odorata), Javan podocarpus (Podocarpus nagi) and state protected species like towering trees (Shorea wangtianshuea), etc.. All trees are prosperously growing in this garden, and make it resemble a natural “ecological park”.

Dai girls picking flowers in the Arboretum