Has anyone ever had this happen? I found some moss growing ON some DW that I've had in my tank for months... the wood is just mopani I bought at petsmart (I liked this piece because it had holes in it, which I stuffed with large gravel to keep some anubias rooted in place). I've only ever had fissidens and flame moss in this tank.. the flame moss was removed about 6 weeks ago because I got sick of trimming it... but this definitely isn't flame moss, it almost looks like christmas moss, but I've never had any moss grow attached to wood or stay that low to it.
You'll have to excuse the lame cell phone shots but you can see it just above the knot in the wood on the lower right
It is growing attached to the wood, it doesn't seem like it just settled there (I don't know how it could have gotten there anyways).