What is a common method of mechanical pest control?

Hand-picking or trapping pests is a widely recognized method of mechanical pest control because it leverages physical means to manage pest populations. This approach involves directly removing pests from plants or the surrounding environment, and it can be particularly effective for larger, more visible pests such as caterpillars, beetles, and slugs.

The advantage of this method lies in its targeted nature; it reduces pest numbers without harming beneficial organisms or introducing chemicals into the environment. This method is often utilized in home gardening and small-scale landscaping where the pest population is not extensive and can be managed manually.

The other options represent different control methods. Insecticide application involves using chemical treatments to eliminate pests rather than a mechanical approach. Biological control agents refer to the use of natural predators or parasites to control pest populations, while soil fumigation is a method of treating soil with gas to eliminate pests, pathogens, and weed seeds. These alternative methods typically involve more complex interventions and do not qualify as mechanical control methods.