Which of the following control methods uses traps and barriers to prevent pest spread?

The method that employs traps and barriers to prevent pest spread is best described as mechanical control. Mechanical control involves the use of physical devices to reduce pest populations or prevent their entry into critical areas. This can include traps for capturing pests, barriers like screens or row covers to keep pests out, and other non-chemical methods that physically hinder pest access or movement.

In contrast, cultural control typically involves practices that modify the environment or the way crops are grown to make them less conducive to pest problems, such as crop rotation or adjusting planting times. Biological control relies on utilizing natural predators or parasites to manage pest populations, which is different in approach and methodology. Physical control, while it might seem similar, generally refers more to non-specific physical actions like removing pests by hand or affecting their environment directly, rather than the use of specific tools like traps or barriers.

Understanding this distinction helps clarify why mechanical is the appropriate choice, as it specifies a focus on traps and barriers as tools for pest management.