Straw is an excellent fertilizer and it also helps to keep the lawn from being torn up in the fragile wet state that winter brings. After having spread grass seed, I broke up two bales and spread it so it makes like a carpet pathway across the lawn. I usually work the grass seed into the soil but with the drought conditions, I did not want to break up the soil in advance because we have been repeatedly promised rains that have never materialized. The straw will help to prevent mud / dirt from being tracked in by the dogs. The dogs have paths around the yard and thankfully, straw eliminates a lot of the muddy mess though the curly coated ADTs will some times bring in pieces of it on their coats. By spring, the straw will have already begun to break down into the soil or the lawn mower will make quick work of the residue thus further enriching the soil.