What situation is best served by using chemigation?

Using chemigation refers to the practice of delivering pesticides through irrigation systems, which can be extremely efficient for several reasons. When pesticides are applied via chemigation, they are mixed with water and transported through the irrigation system directly to the root zones of plants. This method ensures that the pesticide is used effectively, as it allows for a more targeted application where the plants can absorb it more readily.

This approach can help in reducing the overall amount of pesticide needed since it minimizes waste and maximizes coverage. Additionally, it saves time and labor because applying the pesticide can occur simultaneously with regular irrigation, thus streamlining the agricultural process.

In contrast, applying pesticides only to dry soil is not ideal, as the efficacy of many pesticides is enhanced when they interact with moisture in the soil. Using pesticides in unmonitored areas can lead to environmental concerns, as there's a risk of overspray or runoff that can contaminate non-target areas. Lastly, applying fertilizers without water is not suitable for nutrient absorption, as many fertilizers require water to dissolve and make the nutrients available for plant uptake. Thus, delivering pesticides through irrigation systems is the optimal scenario for effective pest management.