How To Reset Landscape Texture If Too Many Applied ?

After making a landscape blend material with about 8 textures I run into a problem. When I apply more than 3 sometimes 4 or 5 textures then my ground goes to the default grid texture. Now I’ve seen in the forums and answers here that I can only have so many textures applied to my landscape before this happens. My question is now that this has happened how can I get my landscape section back to it’s original grass texture it was ? Control Z to undo is not an option as I have already quit UE Application and came back on.

Thank you for taking the time to read and answer my question.
Richie