I am a fan of deep litter. Leaves, grass clippings, AGED wood chips, spent coop litter, garden weeds, hay, and any other yard debris which would compost. The goal is to get that litter 6" deep. Studies show that chickens raised on deep litter have: Improved immune systems, improved feed conversion rates, decreased disease, improved viability, decreased issue with parasites. Deep litter also produces a run which is odor free, gives the birds plenty of dust bathing opportunities, never needs to be cleaned, though you can harvest plenty of rich black, sweet compost from the run for your gardens.