I was gathering some wood a few weeks ago to stock up on spoon carving supplies for the use of and now one branch has white fur growing where the wood was broken... What is this and do I need to be worried about it taking over the whole house/country in some sort of 1950s B movie fashion... In all seriousness I'm just wondering if it's toxic or whatever as I have a cat that wonders around the place licking things he shouldn't.