When Becky was teaching in Relief Society in one of her lessons she was discussing the Relief Society motto and the Relief Society Seal. She wanted to know if any of us knew why there were wheat sheaves on the seal. None of us knew and she didn't either. Anyway, I was curious and thought for sure I could find out why on the internet, but I couldn't find anything. Well this morning I was going over the RS handbook and came across a section on the RS Motto and Seal. And it states....
The seal of the Relief Society incorporates the motto "Charity never faileth" with wheat sheaves symbolizing the storing of grain for a time of need.
So now we know.