Observing cultivated plants is fairly normal behavior for new users who have not thought much about nature and how we relate to it – for a naive user, plants are green growing things and therefore nature. The idea that it is relevant whether a plant was put there by humans or not (and how to tell what sort of plants are generally cultivated) is something that has to be learned.
So users making mistakes in this respect is not a problem specific to the CNC. It’s an ongoing challenge that I think ideally needs to be integrated into an in-app onboarding process for new users. Unfortunately the app development seems to be going in the other direction.
What is specific to the CNC is the volume of such observations, with an additional element of competition that means that users are more likely to just keep making more observations and less likely to see feedback or take it into account. (And they are also less likely to get feedback, because the regular users who might otherwise provide the feedback are overwhelmed with the number of observations coming in.)