What method entails inserting small amounts of pesticide into holes drilled in a tree trunk using a plastic septum?

Microinjection is the method that involves inserting small amounts of pesticide into holes drilled in a tree trunk using a plastic septum. This technique allows for precise delivery of the pesticide directly into the tree, which can be particularly effective in treating specific pests or diseases that affect the tree. The use of a plastic septum helps to create a seal around the entry point, minimizing pesticide leakage and ensuring that the substance is delivered effectively into the tree’s vascular system.

This method is advantageous because it can provide targeted treatment with less pesticide exposure to the surrounding environment, and it can potentially reduce the impact on non-target organisms. By concentrating the treatment within the tree, microinjection can enhance the efficacy of the pesticide, ensuring that it reaches the areas where it is most needed.