What’s special about maple trees?

Sugar made in summer, saved for spring

All summer, a maple’s leaves use sunlight to make sugar. Before winter, the tree stops growing and stores food as carbohydrate (mostly starch) in living cells in its wood. When the wood warms in late winter and early spring, the tree turns that store back into sugar, mainly sucrose, and it dissolves in the sap moving through the wood.

What sap is

Fresh maple sap looks like water and tastes only slightly sweet. Sugar maple sap averages about 2% sugar, so it is roughly 98% water. That is why it takes so much sap to make a little syrup.

Which maples are tapped?

Any maple can be tapped. Sugar maple is the classic syrup tree because its sap is the sweetest on average, and black maple works well too. Other maples, such as red and silver maple, usually have less sugar, and their buds open earlier, which shortens their season.

Want to go deeper? Why does the season end?

As days stay warm and the buds swell and open, the tree’s chemistry changes. Sap flow drops, and late-season sap develops off flavours, often called “buddy” sap. That is the signal the season is over for that tree.

Sources

1. University of Vermont Libraries, Sugar Maple: Sugaring — Physiology. libraryexhibits.uvm.edu
2. Cornell Cooperative Extension of Warren County, Maple Syrup Production. warren.cce.cornell.edu
3. Ontario Maple Syrup Producers’ Association, Maple Products. ontariomaple.com