Photo credit: Dave Pape
Every spring, as temperatures rise, trees start to wake up from their dormancy. They've been storing energy all winter as starch in their wood. But now, they want to use it to start producing leaves. And the way they get that energy to their leaves? Sap.There's a particular window of opportunity for maple sap that is determined by temperature. When the temperature of the wood rises to the mid-30s, enzymes start to convert the stored starch into sugar. And once the tree warms up to about 45 degrees, the starch stops converting into sugar. In between, when days are relatively warm but the nights are relatively cold, pressure builds up in the tree, and the sap comes pouring out of any wounds -- particularly a wound that was put there intentionally to direct that sap into a bucket.
If you taste the sap when it comes out of a tree, it will be only very slightly sweet; the sap is usually less than 3 percent sugar. In contrast, maple syrup is typically around 66 percent sugar. To get from 3 to 66 percent, you have to boil off an enormous amount of water. A single tap may release 10 to 20 gallons of sap from a tree over the several weeks that the sap is running. But that 20 gallons of sap boils down to less than a gallon of syrup. No wonder it's so expensive!
Meanwhile, we'll be curled up by our woodburning stove, watching a little pot of sap collected from our neighborhood maples as it slowly cooks down...the sweet taste of spring on its way!
Do you have any maple syrup stories to share? Leave us a comment.