DETROIT (AP) — Michigan’s maple syrup producers are preparing to get their trees tapped and sap collected, but some say the sugaring season is coming earlier and disappearing sooner than in the past.

The conditions are being attributed by some to climate change, but others say the sugaring changes are a consequence of Michigan’s unpredictable weather.

“Every season is different, that’s what it comes down to,” said Russell Kidd, a Michigan State University Extension district forestry educator in Roscommon. He said no data have been gathered to prove that Michigan’s maple syrup producers are moving up their tapping schedules.

The clear sap inside maple trees flows best when daytime temperatures are in the 40s and nights are below freezing. Once the nights warm up and maple trees start to bud, the sap turns bitter.

“Every year, it seems like it’s getting earlier and earlier,” said Rick Peters, one of about 500 commercial maple syrup producers in Michigan who operates in the state’s agricultural Thumb region. “The weather’s definitely changing.”

Peters said he used to make syrup for 15-20 days, but recently that’s changed to five to seven days.

In the Upper Peninsula, Terry DeLoughary, the owner of DeLoughary’s Sugar Bush in Bark River, said a blizzard prevented him from reaching his trees last month.

Now he is concerned about the possible effect of mild weather. “Say it warms up next week and it just stays warm overnight - you have a little bit of run at the start of it and then you wipe out completely,” DeLoughary said.

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