I much prefer the dried pine shavings we can purchase through our local farmers cooperative. They are screened, so have no fine dust or sawdust that tends to pack, and the chickens love the fresh shavings when we put them down. I don\'t like straw or anything else with hollow stems, as that makes an ideal place for mites and lice to live and multiply. We do use grass hay for nesting boxes, but shavings work OK for that too. No matter what is used, we make sure it gets a sprinkling of 5% Sevin dust, both in the nests and on the floor to discourage the insect pests. It doesn\'t seem to have any harmful effect on the birds. We do sprinkle the \"fines\" of alfalfa hay, consisting primarily of leaves, in the pens for the birds to pick over. Everybody seems to have their own system, but this works for us.