If I manage to get the manure down early enough, say October, I cover with wet cardboard then black polythene, when I come to it in March the cardboard has been taken down by the worms - I read somewhere that the worms like the glue, down know how true that is but whatever the reason the cardboard disappears leaving only plastic tape etc (works really well) If I do it know I just put the black polythene down, as past experience tells me there is not enough time for the cardboard to eaten. However most of my neighbours just leave the spread manure on top of the ground, and that works for them.
That's my take but I am sure others will be along shortly.