Which of the following activities is considered handling of pesticides?

Mixing or loading pesticides is considered handling of pesticides because this activity involves direct manipulation of the chemical products themselves. Handling encompasses any action that involves physical contact with the pesticides, which can include mixing solutions or loading the pesticides into application equipment. This phase is critical because it requires knowledge of safe practices to prevent potential exposure to harmful substances.

The other activities listed do not involve the direct handling of pesticides. Observing plant wellbeing during application is an observational activity that does not require touching the pesticide materials. Using protective gear while planting involves safety precautions but does not equate to handling the pesticides directly. Sampling soil for pesticide residues relates to assessing contamination or residue levels rather than the application or manipulation of pesticides themselves. Thus, mixing or loading is the central activity that defines handling, necessitating appropriate training and precautions to ensure safety.