Climate Effects on the Culture and Ecology of Sugar Maple

Maple syrup is produced from the sap of sugar maple trees collected in the late winter and early spring. Native American tribes have collected and boiled down sap for centuries, and the tapping of maple trees is a cultural touchstone for many people in the northeast and Midwest. Because the tapping season is dependent on weather conditions, there is concern about the sustainability of maple sugaring as climate changes throughout the region. In spite of this, maple syrup production is increasing rapidly, with demand rising as more people appreciate this natural sweetener. 

 

This project addressed the impact of climate on the production of maple syrup. Informed by the needs of state and federal resource managers, tribal groups, and other maple syrup producers, the research team examined sugar maple’s sap yields coupled with the sugar and biochemical composition of sap throughout the geographic range of sugar maple.  Sap quality and quantity was related to historical and projected climate changes across the species range and was modeled for climate change scenarios. The team found that declines and increased variability in sap flow are likely near the southern range limit and increased sap flow is likely at the northern range limit. 

 

The results suggest long term range shifts toward the north, as well as geographic variation in expected syrup production over the next several decades. Using surveys of maple syrup producers, the team also found that producers perceive changes in climate variables and concomitant shifts in sap production.  Many producers are willing to shift sap harvesting practices in response to changing climate scenarios, but producers are split in their perceptions about the importance of individual variables and their level of concern about future impacts on the industry. Overall, the results can be applied to design more effective extension programming and adaptation plans to mitigate the risk of climate in maple systems.