Peggy: The highest priced hay is alfalfa hay. The old saying is "corn is king and alfalfa is queen". Alfalfa hay is a high quality nearly complete feed for ruminant animals. An alfalfa hay field will last 3 - 5 years before it needs to be torn up and replanted. Grass hay (Bromegrass or orchardgrass) will last indefinitely if properly managed. The preferred time to seed a hay crop is the early fall and from your message, I think you realize this. A spring seeding can be successful, if planting is completed by mid-April. For more information on forage (hay), check out the PastureNet it has tips on seeding, and management of hay crops. On that site, there is an article on spring seeding. (
http://www.livestocktrail.uiuc.edu/pasturenet/paperDisplay.cfm?ContentID=8778) If I can be of further help, please contact me.