Which type of pesticide causes injury upon contact and does not need to be ingested?

The correct answer is contact pesticide. This type of pesticide works by affecting pests when they come into direct contact with it. Unlike ingested pesticides, which require the pest to consume the chemical for it to be effective, contact pesticides can quickly cause harm simply by the pest touching or crawling over the treated area. This characteristic makes contact pesticides highly effective in managing a variety of pests, particularly those that are surface-dwelling.

In contrast, ingested pesticides need to be consumed by the pest to result in injury, while systemic pesticides are absorbed into the plant or organism and affect the pest once it interacts with that host. Residual pesticides refer to those that leave a lasting effect after application but do not specifically define the mode of action as contact pesticides do. Hence, contact pesticides are uniquely designed for immediate action upon contact with the target pest.