PUTNEY, Vt. -- After an unseasonably mild New England winter, Vermont residents have been speculating for months about how the weather would affect the state's famed maple sugaring season.
Don Harlow, a bubbly man who has produced maple syrup for 63 years at Harlow's Sugarhouse in Putney, is not one of them.
''If you've ever sugared, you know you don't predict a season till it's over," said Harlow, 73, a third-generation sugar maker. ''Abnormal sugaring is normal sugaring."
After the unusually warm winter -- the National Weather Service says Burlington's average winter temperature of 25 degrees was the 10th-warmest on record -- sugar makers are wondering what's in store for them. For many, last year's crop was disappointing because of the weather.
''Who knows what exactly this season will bring?" said Tim Wilmot, a researcher at the University of Vermont's Proctor Maple Research Center. ''It's always been somewhat unpredictable, but I think it's probably more unpredictable than ever."
The best sap flow comes after nights that dip below freezing, followed by sunny days that rapidly warm the thick maple trees, causing the sap to ''run like a brook," as Harlow puts it.
But Tim Perkins, director of the center, said, ''Sometimes it runs like a brook, sometimes it just kind of dribbles."
Perkins said no one knows what effect the relatively warm weather will have on syrup production. ''We don't have a clue," he said.
Tradition tells sugar makers not to tap until Town Meeting Day, the first Tuesday in March. But during a warm spell in late January and early February, some of them got antsy, tapping earlier than ever. Then the weather turned cold for weeks, and some complained of a slow sap run; a few said there was an off-tasting syrup early on. Others say this year's syrup has a low sugar content, which means it takes more to produce a gallon of syrup. But that has nothing to do with the taste, which Harlow described as ''fantastic."
''The flavor's just terrific," he said. ''It's one of those vintage years."
Even for those sugar makers who waited a bit longer to tap, like Butternut Mountain Farm in Johnson, it has been an unusual season. ''We tapped the earliest we've ever tapped," said Emma Marvin, the owners' daughter. ''We boiled the earliest we've ever boiled."
Paul Greco, owner of Two Old Saps Sugar Works in Lincoln, said that instead of wearing snowshoes to tap the trees while standing on several feet of snow, as he had in past years, this year he carried a pail to put on the bare ground to stand on to place the spouts.
STICKY SITUATION ALL OVER See a video on how maple syrup is produced on explorenewengland.com.
There is some concern that those who tapped early will see their season end early because the sap holes will dry out. But nothing will affect production more than the weather over this next month, Perkins said. Some sugar makers in northern Vermont are just getting going.
It has been a season of fits and starts for syrup production. While Harlow, who recently remarried, was with his wife in Florida in early February, his staff and two sons were tapping the farm's 11,000 sugar maple trees. But before they could get all the trees tapped and he could make his way back to Vermont, the weather did an abrupt about-face. The sap quit running through the network of tubes that weaves through his sugar bush -- acres upon acres of sugar maples tucked behind his sugarhouse and roadside stand.
''It froze up tighter than a barn door," Harlow said. ''It froze up solid for two weeks and never ran a blessed drop."
During the cold, windy days that followed, Harlow fretted at his farm here in the foothills of the Green Mountains and waited for the sun to shine. He spent his days shuttling between his old farmhouse on one side of Bellows Falls Road and the sugarhouse on the other, and driving to the sugar bush to check the tubes and clean the drums where sap is stored.
Harlow shuffles into the sugarhouse kitchen and points to five paper calendars hanging on the wall, his way of proving how widely the sugar season varies from year to year. He points to the 2001 calendar, which is marked with descriptions of the weather and shows that the first day he boiled was March 14, much later than this year's February start.
At his huge farmhouse across the highway, Harlow has 70 years of records, which his aunt started keeping in 1928 and which his first wife kept until her death in 1998. He doesn't spend much time reviewing the data, though. ''It's so darn contradictory," he said. Even scientists can't tell you what it means, he said, only half-joking.
But on a recent weekday visit, the sun was out, the sky was clear blue, and the sap had been running for days. Harlow was in a jolly, storytelling mood -- nothing makes a sugar maker happier than the smell of syrup wafting through the sugarhouse. He waved some steam from the boiling sap toward his face, inhaling deeply. He said the smell always reminds him of coming home on the school bus, seeing the steam rising from the family's sugarhouse, and running to grab one of the doughnuts his grandmother would make for the first boil of the year.
Harlow confides that he sometimes misses the old days. The sap was drained into metal pails, collected with the use of horses and a wagon, and then sometimes boiled on a fire outdoors.
But even today's syrup production is striking in its simplicity. The sap passes through thick plastic tubes, and Harlow carts it in an old milk truck from the sugar bush to the sugarhouse, where it is piped it into a stainless steel evaporator fired by oil. The water is boiled off as it passes through the evaporator's channels, leaving the light, delicious syrup behind. From every 40 gallons of sap comes one gallon of syrup.
Despite the unpredictable nature of his job, Harlow figures history is on his side this year. ''Bare ground years have always given us a whale of a nice crop," he said. And he's hopeful this will be one of those years.
It tends to be a trait of sugar makers.
''When you're at the hands of Mother Nature, you can't curse her. You're apt to get something worse," said Greco, of Two Old Saps. ''You have to take what you get and be satisfied with that."
Contact Kristen Green, a freelance writer in Somerville, at firstname.lastname@example.org.