By: Brian Randall, General Manager and Ben Kraus, Perennials Manager
As ecological farmers, we put a great amount of emphasis on respecting nature and our environment. This means we work with the cycles of nature to the greatest extent possible to ensure we are producing healthy food and developing a healthy ecosystem. One exciting cycle we look forward to each year is the ‘sugaring’ cycle, in which sap is collected from maple trees on our farm and processed into maple syrup.
Maple syrup is made by boiling down the sap of maple trees. When sap is boiled down, it becomes a thick, amber colored syrup. The sap is mostly water, but it contains small amounts of minerals, sugars and other organic compounds. The species of maple tree and the temperature of the sapwood within the tree dictate the flow rate of the sap. As the tree warms to above 32 degrees Fahrenheit the sapwood undergoes a pressure change, which creates the sap flow. For strong sap flow to continue, a temperature cycle above and below freezing must occur.
Tap in a maple tree at Gwenyn Hill
The ‘sugaring season’ is usually late winter into early spring when the days are warm and the nights are cold. For southern Wisconsin the sap from maple trees is normally collected in early March for a period lasting between 3-6 weeks. Unusually warm temperatures in the past few years mean that we’ve harvested sap as early as late January.
Gwenyn Hill’s very own Perennials Manager, Ben Kraus, leads the efforts to collect sap and produce syrup. In 2024, Ben put out 22 taps around the farm. Within 4 weeks he had collected 148 gallons of sap. He processed the sap over three weekends, employing Gwenyn Hill’s ‘Mobile Sugar Shack’ which doubles as our Farmstand ‘Fruit Cart’ during the harvest season. We are nearly doubling the number of taps we are putting in for 2025.
A general rule of thumb when processing sap into syrup is that 40 gallons of sap will produce 1 gallon of maple syrup. This rule, however, is for sap from sugar maple trees, which tend to have a higher sugar content than other varieties of maples. Gwenyn Hill Farm has very few sugar maple trees, but a good population of Silver, Norway and Red maple – and this is what Ben had to work with. The sap from these trees still produces amazing maple syrup, but the sugar content is much lower, which means the ratio of sap to syrup was approximately 63 gallons of sap to 1 gallon of syrup, instead of the standard 40 to 1.
Ben processed the sap in three different batches, which have three different flavor profiles. As the season goes on, the flavor profile and color changes. This change is because of the change in tree biology and microbes breaking down sucrose into simple sugars as air temperatures rise through the season. At the beginning of the season the sap is lighter, with a very light flavor. Each subsequent batch gets darker with a heavier maple flavor.