Small squares best stacked string up or on side

I was wondering what is the best way to stack small squares into a barn? I have always stacked them string down but i have stored verry little hay but i am going to be baling more small squares next year and was wondering what the best way to stack it is and why so I can get prepared over the winter? My bale size as of now is 14x18x36 How does everybody stack it. Thanks.

Small squares best stacked string up or on side