Hello! I'm new to this forum and thought I'd ask my question here. I didn't find answers by Googling either. This morning, I was tending to my flowerpots. I noticed that one of them is growing, what looks like, black hair. It's standing straight up at about two-three inches and is not attached to a plant. This flowerpot had just dirt in it as I had already removed the plant that was previously in there. Any ideas of what this is? I'm stumped.