By design, Ermor has a dominion that kills off the population very quickly, leaving them worthless in terms of gold income and supply. That's one of their main strengths, since they don't need either. Growth scale wouldn't help you much - it's only 0.2% growth per turn per tick, so it's only noticeable in provinces with high population base. In other words, you are stuck with it. Here is a guide that might help you in dealing with Ermor as a novice player (it's for Doms I, but many things will still apply).
http://illwinter.com/defeat_ermor.html
[ November 15, 2003, 21:42: Message edited by: HJ ]