There are light brown granular small insect holes at the base of the side shoots of wintersweet (Chimonanthus praecox). Which pest is this, and how should it be controlled?
There are light brown granular small insect holes at the base of the side shoots of wintersweet. Which insect is causing the damage? How should it be controlled?
This should be damage from the larvae of the leopard moth borer (Zeuzera sp.) tunneling into the stems. The pest had already entered the branches during summer and autumn, but was not noticed when the flowers were selected. After being brought back, the temperature changed and the insects began to become active and cause damage.
Control methods: 1. When branches have already dried up, they should be pruned off, and the insects should be found along the tunnels and killed. 2. Clear away the excrement from the insect holes, and use a medical syringe needle to inject an 800-1000 times dilution of 50% fenitrothion emulsifiable concentrate into the tunnels; alternatively, use a 200 times dilution of 80% dichlorvos emulsifiable concentrate, dip a cotton ball in it and plug the insect holes, making sure to push it deep into the tunnels, then seal them with wet mud. This has a good insect-killing effect.
Control methods: 1. When branches have already dried up, they should be pruned off, and the insects should be found along the tunnels and killed. 2. Clear away the excrement from the insect holes, and use a medical syringe needle to inject an 800-1000 times dilution of 50% fenitrothion emulsifiable concentrate into the tunnels; alternatively, use a 200 times dilution of 80% dichlorvos emulsifiable concentrate, dip a cotton ball in it and plug the insect holes, making sure to push it deep into the tunnels, then seal them with wet mud. This has a good insect-killing effect.