I don't have any examples, just curiosity. Those seem like questions that need answers in order to form a working definition of native plants. Humans manipulated plants for a long time before Europeans. As did animals, weather, geology. Seashell fossils are found on the tops of mountains, things are always changing. It seems difficult to say which manipulation is only good or only negative. Are humans capable of determining positive biomass increase vs. negative? I don't have many answers, but a lot of questions.
