What is the first step to take when investigating potential herbicide injury?

Identifying the herbicide(s) used is the first crucial step when investigating potential herbicide injury because understanding what chemicals were applied and their specific properties is fundamental to diagnosing any injury observed in crops. Each herbicide has unique modes of action, application rates, and potential off-target effects that can result in crop damage. Knowing which herbicides were used allows the investigator to look for symptoms associated with specific herbicide exposures.

Once the herbicide is identified, the investigator can correlate the timing of application with the crop's growth stage and symptoms observed, facilitating a more informed analysis. This information is pivotal for determining whether the symptoms are indeed due to herbicide injury or if they may be attributed to other factors, such as nutrient deficiencies or pest pressures.

Addressing soil quality, weather conditions, and crop variety are also important during the overall assessment, but they come into play after understanding the herbicide application. Identifying the chemicals involved provides a clear starting point for further investigation into environmental factors and plant health.