How do an alliance own a farm?

What is the purpose of a second farm alliance?

Farm accounts exist so that you can attack them yourself and take the resources. You don't want them in the same alliance as you. An alliance may have many members with farm accounts and they will want to put them in a separate alliance that they can control and keep safe.

Can anyone tell me in a farm Alliance what is the best research to do? I hear and have read from what I can find that it is not good to research the compartmentalised storage in a farm Alliance, can anyone help me with this?