First, it'll be used as bedding in the chicken coop. For the past year, we've been using cedar shavings* that were the byproduct of a fence Dakota built a while back. He brought home 6 or 7 large trash bags of the shavings, which we used to line the floor of the coop. It worked really well and, better yet, was free. But, last weekend, the cedar shavings finally ran out, so it was off to a feed store in Burbank for a bale of hay.
Here it is lining the bottom of the coop, before I replaced the removable slatted floor. (That white stuff is diatomaceous earth, which is supposed to keep fleas and other bugs away.)
After the hay has served its purpose as a poop receptacle, it'll go onto its second life as mulch for my summer garden. I found out last year that a layer of mulch can make a BIG difference for my container plants like tomatoes and eggplants. And I know hay is also recommended as a mulch for squash hills.
I already put some hay scraps on my first container tomato of the season. Now that the temperature is rising, I know it'll help the plant stay perky and healthy.
* A note about cedar shavings and chickens: I have read on many message boards that cedar can be toxic to a chicken's respiratory system. That has not been my experience. We used cedar shavings for a year, and saw no ill effects for our hens. I should clarify that our chickens didn't bed down directly in the cedar. It was in a thin layer below the slats of the coop floor. I also know that Barbara Kilarski recommends cedar shavings in her book, Keep Chickens! So, I guess it's an individual choice for each chicken owner to make.