They are an excellent soil conditioner, but they do need to be dug in. We tried them as a mulch once, but they dried out and blew around everywhere. I understand that they have very little fertiliser value.
And I agree about the smell, although it's not too bad when they're fresh. Another mistake we made from the first batch we had was to put some by for digging in at the end of the season. When we eventually opened the bags, I can only liken the odour to that of dog poo. :o
