Texas FFA Nursery Landscape Practice Exam

What describes a systemic insecticide?

1. Kills on contact

2. Applied as a fumigant

3. Absorbed through the roots and leaves of a plant

4. Does not come in granular form

The correct answer is: Absorbed through the roots and leaves of a plant

A systemic insecticide is characterized by its ability to be absorbed by plants through their roots and leaves, allowing it to move throughout the plant's vascular system. This systemic action enables the insecticide to effectively target pests that feed on various parts of the plant as it becomes part of the plant's tissue. Because it is distributed internally, pests that chew or suck on the sap will ingest the insecticide while feeding, which leads to their control. The absorption process distinguishes systemic insecticides from contact insecticides, which kill pests upon direct contact. Additionally, systemic insecticides are typically not restricted to a specific application method, as some may be applied in granular forms or through soil treatments. The ability to be absorbed and circulated within the plant enhances their effectiveness against persistent pests that might evade contact treatments.