What is one of the 4 primary factors to consider when selecting herbicides in aquatic environments?

When selecting herbicides for use in aquatic environments, one of the primary factors to consider is the characteristics of the environment. This includes understanding the specific conditions of the water body where the herbicide will be applied, such as water temperature, pH levels, and the presence of sediment or other substances that could interact with the herbicide. Aquatic environments can have unique ecological balances, and the responses of various organisms to the herbicides can vary significantly based on these environmental characteristics.

By evaluating these factors, practitioners can ensure that the herbicide selected will effectively control unwanted plant species while minimizing potential harm to non-target species and overall ecosystem health. The characteristics of the environment also guide considerations related to the potential for runoff, degradation, and movement of the herbicide, making it critical for effective and environmentally responsible pest management. Other options like soil type and weather forecasts, while relevant in some contexts, are not as pivotal in aquatic settings specifically because they do not directly impact the chemistry and interactions of herbicides in water.