Which of the following are examples of mechanical controls for insect pests?

Mechanical controls for insect pests involve physical methods that directly reduce pest populations or prevent their access to plants, rather than using chemical means. Trapping is a common mechanical method that captures insects, reducing their numbers in a given area. Screening and barriers serve to physically block pests from reaching plants, while shadow devices can manipulate light to deter pests. Sticky bands are designed to catch insects that attempt to climb plants, further reducing potential infestations.

The other options involve different categories of pest management. Pesticide sprays are a form of chemical control, targeting pests with toxic substances. Insecticide baits also fall under chemical controls, as they contain substances that attract and poison pests. Cultural practices pertain to alterations in how crops are managed and can include techniques that promote plant health or disrupt pest life cycles, but they do not fall under mechanical methods. Understanding the distinctions between these categories is crucial for integrated pest management strategies.