Which of the following would not be considered reportable visible evidence of previous treatment?

The identification of reportable visible evidence of previous termite treatments is crucial for pest control professionals. Swarmer wings, while they can indicate the presence of termites, do not directly reflect a previous treatment. Instead, they are typically evidence of active infestation or reproductive activity in termite colonies. Therefore, they do not serve as an indicator that a treatment has been conducted, which is the core aspect of the question.

In contrast, frass (the fecal matter of termites), termite mud tubes, and wood damage are all direct indicators of past or ongoing termite activity and are commonly reported in evaluations following treatments. Frass signifies that termites have been feeding in the area, mud tubes are constructed to provide moisture and shelter for termites traveling between their colonies and feeding sources, and wood damage reflects the destruction caused by termites, all suggesting previous treatment attempts or infestations. Thus, swarmer wings stand out as the only choice that does not signify evidence of past treatment.