Although there are about 150 species in the maple tree family throughout the world it is only in North America, specifically in the northeastern United States and southeastern Canada, that all the right elements of climate and geography come together to provide enough sap to support a syrup industry. Maple syrup is produced from sap from black and sugar maple trees. These trees are the most preferred due to their high sugar content and can be found in sugar bushes or maple-syrup producing farms. A sugar bush is a forested area that contains mostly maple trees.
Trees can be tapped after 50 years of age by boring holes in the trunks. This “opening” of the tree to gather the colorless, almost tasteless “sugar water” occurs in the late winter/early spring. Each mature tree may have as many as four taps. Each opening yields about 10 gallons of sap a year.
Buckets fill slowly, drop by drop, with a sweetish, watery liquid that is boiled down to make the flavored syrup. The tree sap is boiled in a sugar shack or cabane a sucre. During this heating process the clear sap begins in a watery form that contains about two per cent of sugar, it eventually transforms into a high concentration of sugar suspended in water. This explains why it takes about 40 gallons of maple sap to make one gallon of pure maple syrup. It will take anywhere from 6-8 hours until the sugar content is more than 67 per cent it is officially maple syrup.
If the sugarmaker continues the evaporation process, the result is maple honey (a thicker consistency), followed by maple butter (which is thick and spreadable), and, once almost all the water has been evaporated, maple sugar. Maple sugar is about twice as sweet as granulated white sugar. It also browns more quickly, and imparts much more flavor than white sugar.
Making maple syrup requires freezing nights and warm (but preferably not over 50 degree) days. Typically, three or four weeks in early spring, when the nights fall below freezing and the days are beginning to warm up the sap or “sweet water” flows up from the tree roots. Extended periods of either below freezing temperatures or days without freezing nights will stop the sap flow. As a result, sugarhouses often start and stop boiling at different times due to local weather factors. A sugarmaker’s life during tapping season can be unpredictable with 24 hour work days interspersed with two or three days of inactivity until the next sap run. One thing's for sure, when the trees begin to “bud out” the harvesting of sap is over. On average the sap flows takes place for only ten to 20 days, often with up to a third of the season’s yield in a single day.
Today only weekender or boutique tappers still use tin spigots and white pine buckets. Larger operators use a gravity flow system that brings the sap from the trees to a holding tank where it goes through an osmosis unit to remove impurities and about two-thirds of the water. It’s easier and more efficient for the farmer, and has less of an impact on the trees. It allows for a shorter boiling down time, saves time and fuel costs. The next step in the flow is the evaporator, where it is reduced to a syrup, and takes on its typical rich coffee hue. Large sugarhouses can process as much as 1,700 gallons of sap an hour. The final step is a boiling in a sterile stainless steel tank.
A Sugarbush Tale 11minute documentary on of sugaring (awesome!)