Warm winter and maple syrup
UNIVERSITY OF MINNESOTA EXTENSION - www.extension.umn.edu
Some maple syrup producers might be concerned about winter warm-ups and sap flowing early. Most large producers in northern Minnesota base their schedules on the calendar— tap in February to be ready by March 1. Producers in the Twin Cities or farther south can be 10 days to two weeks ahead of that schedule.
It is possible that the trees will drip with an early warm-up, but the first thaw is almost always a teaser. History says our sap runs happen between March 15 and April 15. Plenty of time for us to still get some real snow and cold.
The large commercial maple syrup operations will likely wait to tap the majority of their trees. The hobbyist with less than 10 trees to tap may consider tapping during a warm-up, but it may be a short sap run.
Sap begins running when the temperature is mild or above freezing during the day and freezing at night, but it’s a small window. If temperatures drop below freezing during the day, the sap will stop running. If it’s too warm during the day (above 55 F) and temperatures remain above freezing at night, the sap dries up.
We recommend making only one tap per tree. If you decide to tap now during this likely short sap run, try tapping a different tree later in the season.
