Will My Mondo Grass Take Over My Fescue Grass?

Q: I have fescue grass with some mondo grass mixed in. Will mondo grass eventually take over the fescue? 

A: The amount of light the area gets would determine which plant would win. In moderate to deep shade it is likely the fescue would thin out and the mondo grass would gradually take it over. Conversely, with more sunshine the fescue thrive would thrive and the mondo grass would be slowed substantially.