Pest Control Technician Practice Exam 2026 - Free Pest Control Practice Questions and Study Guide

The distinction between contact and systemic insecticides is fundamentally based on their mode of action and how they interact with pests. Contact insecticides are designed to kill insects upon direct contact. When applied to the target area, these insecticides affect the pest immediately or soon after contact, making them effective for controlling infestations that are visible on surfaces.

In contrast, systemic insecticides are absorbed by plants through their roots or leaves and then translocated throughout the plant's tissues. This means that when pests feed on the treated plant, they ingest the insecticide, which then disrupts their normal physiological processes, leading to their death. This method is particularly useful for controlling sap-sucking insects such as aphids and leafhoppers that might not always be in direct contact with a surface treated with contact insecticides.

Understanding this difference is vital for integrated pest management, as it allows technicians to choose the appropriate type of insecticide based on the specific pest problem being addressed and the environment in which the treatment is administered.