I am experimenting right now because I felt bad just throwing my duck litter in the trash, it wasn't breaking down enough for me to add it to the garden, but was getting too wet and had too much excrement to stay in the run. I don't think my ducks are cut out for deep litter, however there is hope with the chickens, because, as mentioned, they scratch and turn everything and are a bit drier. So now, when the litter in the duck run needs to be changed, I shovel it all into the chicken run. Then the chickens commence their work turning and picking through it and helping it break down. So far it has been working. By the time the duck run needs to be emptied out again, the chickens have broken down virtually everything and are ready to start their work on the next batch.