check out the contact area : Zoltan E. Pali Somis Hay Barn
there are some pics that scroll in his contact area ... plus a nice
artsy sketch of it.

the hay is stored around the outside of the barn under an
overhang...so the hay walls get used and replenished and they change
the wall colorations according to the season, a very nice simple
design. Not for an area with driving rains however...