Using the “Rule of 86,” you can figure that the number of gallons of sap you need to produce one gallon of syrup is equal to 86 gallons divided by the percent of sugar. So if you start with sap that is 2% sugar, you would need to evaporate 43 gallons to water (86 gallons / 2% = 43 gallons) to make one gallon of syrup.
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How many gallons of sap does it take to make maple syrup?