If this fleece has been in storage for a while, it could have moth larva in it. Keep it outside, and bring in a trashbag at a time (or whatever you have room for) and place in freezer for a few days to kill any insects. I learned the hard way--I, too was given some lovely (at first glance) fleece, and ended up with moth damage all thru my own fiber stash.
Brenda, I've been told that you can just keep it in large sealed bags and put in some moth balls and that will keep the bugs out and kill off the live ones & larva in the fibers. Moth balls give off a gas as they age, hence the reason they get smaller and smaller.
I am sooooo very jealous:)
Yes, I know about using mothballs, but prefer not to have the chemicals in my wool. Freezing works well for me. I also try to wash fleeces asap after they've been in freezer, too.