Thank you for the reply. I was just returning here because I figured out what I did and how to restore it if you do not ctrl + z immediately after a delete of terrain.
What happened was I was clearing some hand placed trees by selecting them in the scene and then pressing delete. I recommend that designers that want to clear their hand placed trees delete them out of the hierarchy. This is because if you are click delete, click delete you might accidentally click on the terrain and then press delete. OOPS! My issue was I forgot the ctrl + z and just left the project and tried to reload it and when it asked me if I wanted to save the scene, I did.
The remedy was to pull the terrain asset out of the assets folder directly and dragging it into the scene without terrain. Just like you do when you hand plant a tree or object. It only works if there is no terrain present as far as I can tell. At any rate I was able to salvage my holes and the terrain and learned the best practice for deleting large amounts of objects out of a scene. Use the hierarchy!
Forging ahead, yeah I went there,
SC