I think that any landlord will want the going rate for crop land. Either as hay or cash.That you will find from  other farmers, landowners ,fsa office. Lots of ways to find the rate for your area.  Landowners  will also need something extra for the risks they are now taking versus cash rent. Why any landlord would want to crop share hay is beyond me.Too much risk. few bad rains and they get nothing.  Maybe in Arizona or someplace the weather may cooperate.Do the landlords need the alfalfa? Do they intend to sell it. How are you going to keep it seperate,this is a multi-cut crop and each cutting will have it's good and bad.  Who's idea is it to crop share?  Cash rent it and be done.

  That all said if you can keep them happy more power to you. No crop shares of hay in the area that I am aware of. Most who want Alfalfa simply like the grass and rent is not a determining factor. Like to look out their window across a meadow. the rest is  cash rent  and the farmer plants what he wants. Most land owners don't care what you plant as long as you pay the rent. Others such as retired farmers like to know whats going on. The city guys are much easier to rent from. See them once a year if at all. Some we have never met.