Virginia Commercial Pesticide Applicators CORE Exam

What is a common characteristic of secondary pests?

1. They require control at all times.

2. They need control only under certain conditions.

3. They are the primary pests in agriculture.

4. They do not affect crop yields.

The correct answer is: They need control only under certain conditions.

A common characteristic of secondary pests is that they typically need control only under certain conditions. Secondary pests are not usually detrimental to crops on their own, but their populations may increase and become problematic when the populations of primary pests are reduced. This can happen when pesticides are applied, as these may target primary pests more effectively, inadvertently allowing secondary pests to thrive without competing pressures. Therefore, their management becomes important primarily when certain environmental conditions favor their growth, such as changes in weather or the reduction of competition. In contrast, other characteristics indicated in the options do not accurately describe secondary pests. For example, the idea that they require control at all times is incorrect, as most secondary pests don’t present a constant threat. Likewise, labeling them as primary pests misrepresents their role in the ecosystem, and stating that they do not affect crop yields overlooks the potential for their populations to escalate and cause damage when their natural checks are removed.