First off let me say I am pretty sure I know what I am going to plant.  I want other opinions though because I see the situation from a distinct perspective while others may see something I am missing.  

I farm several hundred acres which is for the most part planted in alfalfa hay which I sell to mostly horse owners for feed.  I am my only employee so I am about maxed out on what I can take care of farming wise because my other sources of employment take up the remainder of my time.  I am getting ready to replant alfalfa in a 40 acre field that was planted in barley for the last 2 years.  

With the economy the way it is now and if you were making the decision:

Would you plant hay this year on the 40 acres to sell to horse owners?  Keep in mind most of the hay is sold for pets and/or hobby farms.  I have never had any problems selling every scrap of hay I have ever put up and I always sell out well before spring.

OR

Would you scrap the alfalfa planting plans and plant wheat or barley again because human food will be more profitable/desirable in the near future?

I would probably plant the Alfalfa but then again im a horse lover

the horse industry is DOWNNNNNNN.
people are ditching equines left and right.

i would plan on alternatives. not saying dont plant the alfalfa. maybe not an entire 40.
i make my living in the equine world, nationwide.

contact you local stockyards to find out if people have been selling off horses in numbers larger than 2 years ago before you decide. talk to some equine vets as well to verify that your area hasnt been hit.

on one hand, I dont think your 40 acres of human food will make a difference - this year.  Ask again next year.

On the other hand, horse owners won't have enough money to buy your alfalfa hay this year unless you lower price.  So sorry I coudln't recommend one over the other.  It's so close, I'd say if you can combine the wheat and save it, do that.

I deal with a lot of horse owners in my business.

This has been an unbelievably dry year in Colorado, hay is going to be 8 to $10/small bale this summer, premium grass hay.

I'd grow grass hay if you can, and truck it south.
Depends on where you are in MT of course, but unless we get a monster wet april, there is simply no moisture in the ground.
Growing any hay here is going to be tough and it's going to get top dollar.

This is a darn good question to ask.
I'd go with alfalfa for two reasons, despite the down horse market (which is reality in my area, as well)-
1. You're already set up for it
2. You already have a developed market

The only thing that would sway me is if I thought I might need the food for my family. I wouldn't raise wheat with a profit motive in mind considering that you'll most likely be able to sell the alfalfa at some price (barter, whatever).

-Hobbit

I have a horse and know well how down the market is.  Fortunately I'm not in a position financially where I have to sell him, and since he's older and arthritic I'd elect to have him euthanized instead of ending up on a truck to a processing plant in Mexico or Canada.

That said, I'd suggest that you call your customers and ask how much hay they're planning on buying this year.  If they haven't decreased the size of their herds then I'd go ahead and plant the alfalfa.

Hay is always going to have value... if things go completely south, the folks with horses will be the only ones travelling very far.  I can think of lots of things I'd barter for good hay.

On the other hand, wheat is good... thing is, do you have the equipment to harvest it yourself, or would you have to depend on someone else? I know wheat can be harvested by hand, but that's real work.

If you were to break up your alfalfa fields and planted wheat, you'd have to replant the alfalfa if you wanted hayfields in the future.  I'm not as familiar with alfalfa as I am southern grasses... but can't you plant an alfalfa field, and only have to fertilize each year (not replant every year), to get cuttings.  So, if TEOTW arrived, and you had alfalfa, next year you'd still have some alfalfa growing... plant wheat, and next year just native grasses.  Some alfalfa would be better than some grasses...

Plant the hay, and buy wheat this summer with some of your hay money if you wish.  Even if your horse market is hurting, there is always a market for hay with cattle, even if its not as pricey as the one for horses.  Every year I hear about farmers somewhere needing hay.  In terms of profit dollars, you will do better with the hay I believe.