Java Moss Going Nasty

[Bugdozer]

I have a bit of bamboo cane with java moss growing on it. Since acquiring it, more and more of the moss has gone brown and dead looking, though there are still many green tufts on it. Now it looks like all the moss closest to the cane it's growing on has gone brown. I'm worried this dead moss will rot and add ammonia to my tank, I also think when I remove it to hoover the gravel around it, it smells a bit nasty too. Does anyone have any ideas on if it can be restored and is it doing harm to my tank? And what could have made it go like this?

 

[Bugdozer]

Update: I tried to trim the manky moss off the stick and it all came off in a thick mat of dead foliage. So I pulled off some of the living moss and tucked it in a crack in my driftwood piece, where it will hopefully take root.

 

[Box]

Best thing to do mate.
It will grow back after a couple of months