Quick! Can you remember how many maple seeds were helicoptering over your head this past spring? Was it more than the year before? Knowing this might be helpful in predicting if and when pancake-lovers everywhere could face a disastrous shortage of real maple syrup.
"Weather affects how much sap will flow out of the tree, but sap volume is only one piece of the puzzle," Josh Rapp, a researcher at Tufts University, said in a recent release.
Rapp helped senior researcher Elizabeth Crone author a study about predicting the sugar concentration in sap yield per year that was recently published in the journal Forest Ecology and Management.
According to the researchers, syrup producers and experts alike have been using weather patterns - namely annual precipitation - to help predict what kind of sap output to expect.
However, they quickly found that "weather alone was a surprisingly bad predictor of how much sugar came out of the taps," Rapp explained.
He and Crone analyzed the factors influencing 17 years of maple syrup production at 28 sites in Vermont, finding that weather-based predictions of syrup yield was never really spot-on.
"That tells us there is something else at play." (Scroll to read on...)
That's why the researchers turned their attention to "masting" seeding events - years when sugar maple trees produce an uncharacteristically massive number of seeds. Interestingly, it was found that these events occur every two to five years and can be traced to poor syrup yield the next time producer tap their trees.
"Both seeds and sugar are made from carbohydrates stored in trees," Crone explained. "When a tree produces a lot of seeds one summer, then the next spring, the carbohydrate bank account is low for making sugar. It's a matter of budgeting resources."
Rapp adds that these findings could help syrup producers plan ahead for years with poor yield.
"Maple syrup is a complicated natural resource," he said. "Hopefully this research can give producers a window into the upcoming season."
It still remains to be seen exactly what influences the timing of these massive seeding events, but it is safe to say that they are significantly more predictable than the weather. And looking at this year's seeding numbers, 2015 looks to be a good year for pure syrup supplies.