Insect Pests of Tropical Malaysian Urban Trees

Abstract

Urban trees provide many benefits to the well-being of communities. While trees can be resilient and adapt to the challenging growing conditions in urban areas, prolonged exposure to multiple stressors can affect their growth and development. Open wounds and injuries on an already stressed tree, from natural events, accidental or intentional damage, could become entry points for insect pests to enter the tree, which might exacerbate tree decline. Wood feeders can cause substantial damage to the vascular tissues of trees, and their attacks are usually not visible in the early stage or when occurring below ground as in the case of subterranean termites. This chapter explains the damage to different parts of urban trees caused by wood-, leaf-and sap-feeders. In each feeding guild, examples of the common insect pests, their associated host plants, and signs of infestations are given. A combination of management strategies including cultural, mechanical and biological controls can be practiced to improve tree health as well as enhance populations of natural enemies in order to reduce the usage of insecticides, particularly broad-spectrum insecticides that can also kill beneficial insects. Additionally, the termite baiting system developed based on the feeding behaviour of termites, targeted the species of Coptotermes specifically, can be applied on termite-infested urban trees with minimal risk on non-target organisms. Regular monitoring for tree abnormalities should be emphasized in urban tree care to facilitate the early detection and intervention of any plant disorders.