WISCONSIN (AP) — This year’s warmer winter temperatures have allowed some maple syrup producers across the U.S. to begin tapping their trees as much as two months early.

In Wisconsin, the fourth-largest maple syrup producing state, many farmers started production in January and February, earlier than they can ever remember doing it.

Jeremy Solin, who farms a forest first tapped by his family in 1917 in Deerbrook, WI, said typically they wouldn’t be talking about tapping trees until March and that he is concerned about the long-term impact of climate shift on the health of maple trees.

As climate change leads to warmer temperatures, these unpredictable winters may become more and more common in parts of Wisconsin. But many producers are committed to the traditions that strengthen their bonds with their “sugarbushes,” making this practice more resilient than others that are threatened by the slow melting of the North American winter.

Experts say that the shift in maple syrup season could be one clear indicator of the ways climate change is affecting trees, but they also think the practice serves as an important motivation to preserve forests. Producers have deeply personal ties to their land, whether they are Indigenous producers serving their community or have family-run operations and want to leave a legacy for the next generation. That relationship between people and their maple trees may ultimately make people more willing to adapt and be resilient in the face of seasonal changes.

With the arrival of spring, maple trees start to “wake up” from the dormant state that keeps them alive through the winter. But during the critical few weeks of early spring where it’s above freezing during the day and below freezing at night, the trees use their sugar in sap as a kind of antifreeze. Humans have been taking advantage of that process for millennia, collecting the clear, watery sap that flows in early spring and boiling it down to condense it into maple syrup or maple sugar.

But timing is everything. Tapping the trees too soon, especially with the spile-and-bucket method, doesn’t work, because the holes start to close up after a few weeks. The more common commercial method, which involves a series of plastic tubing often called “lines” that snake from tree to tree and ferry the sap in huge quantities, is a bit more forgiving of tapping early but still requires strategic planning.

That’s why producers were caught by surprise this year — they typically plan for mid-March or April, but as they checked the weather this unprecedentedly warm January, they realized the sap had already started flowing. About 40 miles away from Solin, syrup producers missed the first run of sap on Bodwéwadmi Ktëgan, the farm of the Forest County Potawatomi tribe. Joe Shepard, the assistant farm manager there who’s lived in northern Wisconsin his whole life, said he can’t remember a winter like this, with no snow.

Neither can Karl Martin, dean of University of Wisconsin-Madison’s Division of Extension. Martin’s family taps about 4,500 trees, and this year they lost out on about 25% of their production.

With drier summers and less snowfall contributing to groundwater, Solin, who also works for the University of Wisconsin’s division of extension, says the unpredictability is the biggest challenge for sustaining maple syrup operations like his. And the lengthening of the trees’ growing season, with an earlier start and later end to warmer weather, could affect the sap too. So Solin is concerned about water, about the increasingly dry summers in his area and what that could mean for continuing to make quality syrup.

He thinks that producers with smaller operations, and particularly Indigenous producers, will be well-suited to handle the changes that are coming. And the trees, too, especially older, more established trees, will find ways to adapt.

That’s something Forest County Potawatomi members working on Bodwéwadmi Ktëgan are prioritizing: finding innovative ways to produce food independently in pursuit of food sovereignty. Shepard explained that his area is considered a “food desert” — the nearest Walmart is 45 minutes away — and having fresh food to provide for elders in the community is a project they hope to expand. That includes maple syrup and sugar, which is a traditionally important product for some members.

On the spectrum of maple syrup producers, Solin places himself on the end most concerned about climate change and what it may mean for the future of his area. But as he walks beneath the trees, taking the metal cover off each pail, he feels gratitude for the recurring, in-depth experience with his sugar maple grove. It’s the best way, he says, to intimately, or even obsessively, watch the changes in the weather from year to year.

With his family warming up in the sugar shack that pumps sweet-smelling steam into the sky, he gets to take walks here beside the imposing 250-year-old sugar maple his family calls Grandpa Tree. And for another season, he gets to watch as the forest springs back to life.