It's early March, and that means the sap is running - it's maple sugar time at the Indiana Dunes National Lakeshore.
Each year, the Maple trees in the sugar bush of the Chellberg Farm are tapped for their sap. The sap is collected in galvanized buckets and transferred to the sugar shack for processing.
The sugar shack has a large wood fired boiler where the sap is boiled down until the water content is reduced. Around 40 gallons of sap are needed to make 1 gallon of maple syrup.
Gallon jugs are hung above the boiler to warm them. Warming the jugs this way, slowly brings them to the temperature of the syrup. When the hot syrup is poured into the warmed jug it will not break. However, if the syrup was poured into a cold jug, it would quickly shatter.