Tonkin longhorn beetle

The Tonkin longhorn beetle (scientific name: Tocama tonkinensis) is a wood-boring insect belonging to the family Cerambycidae. Known as a significant pest in specific geographic regions, it primarily targets weakened or stressed woody vegetation, making it a critical concern for forestry and arboriculture specialists.

This species infests a range of woody host plants. The severity of the infestation is often higher in managed forests or orchards where trees have been compromised by environmental stressors, such as drought, poor soil quality, or mechanical damage to the trunk or branches.

The life cycle of Tocama tonkinensis is characteristic of many wood-boring beetles, consisting of eggs, larvae, pupae, and adults. The larval stage is the most destructive, as larvae bore deep galleries into the cambium and xylem layers of the host plant, effectively cutting off nutrient and water supply.

Damage symptoms include the presence of frass (sawdust-like excrement) around entry holes, canopy dieback, and bark cracking. If left untreated, the cumulative damage leads to structural failure of the tree, creating severe losses for timber production or orchards. Infested trees often become attractive targets for secondary wood-decay fungi.

Effective management requires a strategic integrated pest management (IPM) program:

• Regular inspection of woody plant health and the immediate removal of infested trees.
• Targeted insecticide applications to prevent adult beetles from laying eggs on the bark.
• Promotion of tree health through proper fertilization and irrigation practices.
• The use of pheromone-based traps to track and suppress local populations.