What is an example of preventive use of pesticides?

The choice of preemergence pesticide use as an example of preventive use of pesticides is accurate because this method specifically targets pest development before they become a problem. Preemergence pesticides are applied to the soil or on plant surfaces to create a protective barrier that inhibits the germination of weed seeds or to disrupt the life cycle of pests before they emerge. This proactive approach helps prevent pest populations from establishing, thereby reducing the need for more reactive or curative measures later in the season.

In contrast, post-emergence application refers to treating pests after they have already emerged and established, which is more of a reactive method. Spot treatment typically addresses specific areas that are already infested rather than preventing future infestations. Annual spray is a general maintenance strategy that may or may not be preventive depending on timing and application method but does not specifically target the prevention of pest establishment as preemergent applications do.