Hi, Actually what I’ve done on my plot is use sheep wool which is used by organic box scheme is using to insulate veggie boxes. So this might be good source of clean sheep wool if you do not have a big area to cover.
As a matter of fact you can see how it looks and I use it on my video here https://www.youtube.com/watch?v=IcU651Yzvfc now looking from perspective of few weeks I can say that sheep wool is good at covering young weeds but couch grass horse tail and other perennials will still go through and have to be removed by hand.
It does great job with retaining moisture which is great for strawberries for example.
It supposed to repel slugs as well but I can’t confirm that as my strawberries just start fruits now.
I also have a lot of birds visiting and grabbing wool to build their nests so I guess it benefits wildlife 🙂