In a sure sign of spring, tree sap for maple syrup is starting to flow.
But just how long it will last and how quickly it will flow depends on the weather.
Warm daytime temperatures followed by freezing weather at night have been the perfect scenario to start tapping tree sap to make maple syrup. This year's syruping season, which usually would have started at the beginning of March, was delayed until this weekend because of the cold weather.
Chris Ransom is a hobbyist who taps about 60 trees on his lot and neighbor's lot in Vadnais Heights. He is also president of the Minnesota Maple Syrup Producers' Association, which has more than 130 members.
It can be difficult to predict how fruitful a maple syrup season will be because the time to collect sap is typically two to four weeks, and weather patterns vary from region to region, he said. An average year would allow him to make 15 gallons of syrup, which he gives away to family and friends.
"I'm on track for a normal start to the season," said Ransom. "But sap run is entirely weather-related — quantity and quality. Last year was a good year for me and for producers from about the Twin Cities and further south. Farther north they had a tougher go of it."
Tree tapping is also in full swing at the Minnesota Landscape Arboretum in Chanhassen, where more than 400 maple, black walnut and birch trees will produce thousands of gallons of sap. The painstaking boiling-down process takes 35 gallons of sap to make one gallon of syrup. In 2017, the arboretum hit 130 gallons of syrup, the most in nearly four decades.
The large amount of snow that fell this winter doesn't appear to be affecting sap flow, said Richard DeVries, who is in charge of sap collection. Almost all the trees were tapped this weekend using several different methods. On half of the trees, a gravity system pulls the sap downhill. The other trees are attached to a vacuum pump that carries sap to a large vat — the more efficient method used by commercial producers. The sap is then boiled in a large stainless steel evaporator that can cook up to 80 gallons of sap an hour.