I am using speedtree while building my course and everything appeared fine until I went and loaded a previously saved terrain. When I looked at the plant set in the inspector there were no speedtrees. When I went back to the current terrain everything looked normal.
Why do I lose those trees in the plant set if I load a previously saved terrain ? I'm talking now about the inspector and not the terrain which I know would not include any trees planted after the date of the prior terrain save.