RE: Another great news for tree lovers: Prague will plant one million trees
It just has to do with the fact that we have been cutting down trees for very long; some of these areas have been regularly logged since the viking ages. This allowed enough time for interesting species to show up, and at this point we consider these species to be as important to the flora as the trees. Even though they might not have been here if it had not been humans in the area.
It raises an interesting questions; at what point should we consider it to be "pristine"? Many areas around the world has had humans interference for thousands of years, and it does not really make sense to strive towards a goal of making the area be how it was before this point. The agreed upon number in Norway is 200 years ish, but it might be very different in other parts of the world.
We only have very small patches of "real wilderness" here in the sense that real wilderness has never been logged. So it probably does not happen there. There small areas have a very different ecology compared to the areas that have been logged in the last few hundred years, so these are strictly protected from logging now.
"It raises an interesting questions; at what point should we consider it to be "pristine"?"
This a very good point actually. Just like you said, way too many natural places around the world have already been modified by humans and the very original, pristine wilderness might now be restricted to just several small areas. Which is sad in my opinion. I generally don´t like it when people interfere with nature too much. In my country, for example, we have been having serious problems with the bark beetle because decades ago, during the communist era, then environmental "experts" were, for some reason, planting only spruces and when the bark beetle disater struck now, the entire forests have to be cut down. Typical example of human interference with nature going wrong.