I know this idea is kind of ridiculous, but my first idea was incredibly boring and "thing what does a thing"-y so I'm trying something a little more zany this time (hopefully in a good way).
The idea is a group of a few dozen trees that can all emit and hear auditory (English) Morse code signals. Most of their time is spent having ordinary conversation, but they speak about humans with hatred and resentment for political (to trees, anyway) reasons such as deforestation.
When a new tree gets planted by the rest of them, it can talk as well. Eventually, looking for answers, the Foundation allows a planned conversation/interview with the trees. The trees say that trees used to be the dominant species until humans took over. At the end, they reveal that all trees can talk, and a nearby (believed to be non-anomalous) tree finishes the interview with the famous quote, "If a tree falls in a forest and no one is around to hear it, does it make a sound?"
The idea came to me really suddenly. I don't know if it's too stupid, too predictable, or both. Does it already exist? Whatever you think, let me know. Thanks.
Edit 1: Thanks for the feedback so far. I fixed a few things I neglected to mention.
Edit 2: Some more stuff.
Edit 3: And something else.