Maple Syrup Season Approaches (updated Mar 7th)

Ready, Set, and Tap...


Maple syrup season is rapidly approaching northern Michigan. The weather expected across the state this week will be nearly perfect for the first run of the spring sapping season. Each spring thousands of gallons of pure maple syrup are produced across the northern Great Lakes - including right here in Michigan. Maple syrup is produced by boiling sap. During the boiling process water is evaporated from the sap leaving a sugary substance known as maple syrup.

Sap is basically sugar water used by maple trees to generate leaves. Sap runs through the roots, just inside the tree bark, to the canopy above. Sap begins to flow during late winter (usually the first week of March), when the sun rides higher in the sky, warming the side of the tree and roots. Sap runs best on sunny days with temperatures warming from morning lows in the lower 20s to afternoon highs in the lower 40s.

The table below shows temperatures expected across northern Michigan through the weekend, which suggests nearly perfect conditions to begin the sap flowing across northern Michigan.


  Low Temp High Temp
Friday 9-15 37-41


19-25 37-43
Sunday 29-34 36-45
Monday 23-27 29-37
Tuesday 16-23 28-35

Interesting maple syrup production facts:

Sap in northern Michigan usually begins to boil between temperatures of 208F and 210F degrees depending on the atmospheric pressure. During periods of high pressure sap begins to boil closer to 210F degrees.

During the earliest stages of maple syrup production, boiling sap looks and acts a lot like boiling water (large rolling bubbles). During the later stages of production, after most of the water has been removed, the sap turns more golden in color, and the boil trends toward a honey comb pattern (small tightly packed bubbles).

During the boiling process, when the liquid boils consistently 7 to 9 degrees above the original boiling point, the process is considered complete, and the liquid has become pure northern Michigan maple syrup.

In the last stages of maple syrup production, the steam rising from the pan smells sweet and is sticky.

Interesting tapping facts: 
are usually tapped on the south side of the tree where sun warms the trunk early in the day helping the sap to flow quickly.

The most productive place to tap a tree is between a main root and large limb in the above canopy.

 Interesting sap facts:

Sap is mainly water with only a small part being sugar. The ratio of sap to maple syrup is high - generally 30 to 60 gallons of sap to 1 gallon of syrup.



The ratio of sap to syrup is best during the beginning of the season when sap has the highest concentration of sugar.





Return to News Archive is the U.S. government's official web portal to all federal, state and local government web resources and services.