Which of the following defines chemical control?

Chemical control refers to the use of substances to manage pest populations, and it encompasses a broader range of products than just pesticides. While pesticides are indeed a significant component of chemical control because they are specifically designed to kill or inhibit pests, chemical control can also include substances that repel pests or attract predators that help manage pest populations. This comprehensive definition captures the nuances of pest management, as it recognizes various chemical products' roles, including those that do not directly kill pests but still function effectively within an integrated pest management strategy.

By contrast, some options do not fit the definition of chemical control. For instance, the focus on only pesticides is too narrow and excludes other relevant products that are vital to effective pest management. Additionally, physical barriers provide a non-chemical means of pest control, and natural substances that enhance plant growth do not directly pertain to managing pest populations. Therefore, understanding chemical control as a multifaceted approach is essential for effective pest management in cool-season turfgrass.