Probably the LEAST used places for grain is in bedding borders and along fencelines. People want to keep things "neat and tidy" but using that space really counts! A bit labor intensive if you are harvesting by hand. Also a very nice background grass for flowers in beds.
I just finished seeding half the chickens run with lettuce/spring rye/wheat for them to pluck on. They can have at it when it grows a bit. My sunflowers won't go in for another week and in triple the amounts as I am going to be feeding goats this year too.
A winter crop such as winter rye can be alternately or interseeded with rapid harvest plants such as lettuces/mustards. I don't know about rape for chickens, we're very restricted about planting rape here. How about millet? This seemed like an interesting paper on it:
http://www.ingentaconnect.com/content/klu/trop/2000/00000032/00000005/00278647
When the chickens have at the half of the run that is planted, I will plant the other half by just tossing mixed seed out there and covering it up lightly with a rake, etc. I'll keep that going back and forth for them, letting them mix up the ground, scratch and peck at it, poop all over it, then I will move them to a third run on the opposite side of the coop. I will plant that area in good grass and let it grow while they are in the third area. When it is established, I'll put them on it and when they have torn it up sufficiently, the process will start all over again. It won't get too pecked and scratched this year with only 4 hens, but next year there will be more
You really got me thinking about chicken feed now! I can't wait to take the poultry nutrition class next term!