TEMPLE, N.H. (AP) - A mild winter across the Northeast is injecting extra uncertainty into maple syrup season, but many producers say they'll just go with the flow, whenever it starts.

Temperatures have been up and snowfall totals have been down, raising concerns about the maple syrup crop. But producers say the weather during the six-week season when sap flows matters more than the weather leading up to it.

Below-freezing nights followed by warm days are necessary to start the sap flowing. Those conditions have already arrived in some areas, prompting some producers to start tapping their trees weeks earlier than usual. The season could end early, too, if prolonged stretches of warm weather result in budding trees.

Last year, U.S. maple production, led by Vermont, hit an all-time high of 2.79 million gallons.