In pest management terminology, what is a residual pesticide?

A residual pesticide is designed to remain effective for an extended period following its application. This characteristic allows it to provide ongoing protection against pests, as the active ingredients remain active on treated surfaces for some time, which is beneficial in maintaining pest control in various environments. This long-lasting effect means that the pesticide does not need to be reapplied frequently, reducing labor and potentially minimizing chemical exposure for both the applicator and the environment.

The other options do not accurately describe the nature of residual pesticides: the first option refers to a short lifespan, which contrasts with the very definition of a residual pesticide, while the second describes a lack of residual effect, and the fourth suggests ineffectiveness after the initial application, which does not align with the intended use and effectiveness of residual pesticides.