Last fall we had an infestation of ivy in our backyard. We tried spraying it with vinegar, but it didn't take out the pesky plant. As a last resort, my husband sprayed it with RoundUp Poison Ivy Killer. I have now realized that a large area of our moss is dead near where he sprayed. I am devastated because I loved the moss and prefer it over grass. How can we get it to regrow? Will we have to dig it up and replant or will the surrounding moss that is alive eventually take over? Thanks!