Spring is coming. How do I know? Certainly not because of the weather outside—it continues to be frightful this year! I know because Maple Sunday is coming right up on the 23rd! The sugar in maple sap only appears when warm, sunny days and below-freezing nights follow each other for days on end, as they do during Maine’s long, slow spring. It is quite a treat to go to farms all over Maine on the fourth Sunday in March. You can experience the process and see a real…