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2015 Maple Sugaring: How’s Your Sugar Content?

The story of this sugaring season may come down to the sugar content of the coming sap flows. Why you ask? Because there is a direct correlation between how much sap it takes to make a gallon syrup and the sugar content of the sap from which it’s being made.

The volume of sap required can be calculated using a nifty rule – Jones Rule of 86. Developed as a rule of thumb for sugar makers by C.H. Jones in 1903, the simple calculation – divide the sugar content of the sap into 86 – has become a part of nearly every sugarhouse. The rule, published in humorous verse in the 1946 Maple Digest, works best in a fairly low and narrow range. Today, with reverse osmosis and other technologies Proctor Maple Research Center suggests that folks might be better off to use the rule of 87.1 – dividing the sugar content into 87.1 and then subtracting 0.32. Using either of the two equations will get you relatively close to the amount of sap required.

At the start of the season this year at our sugarhouse the first couple of runs averaged a sugar content of 1 percent – meaning that it’d take approximately 86 gallons of sap to make one gallon of syrup. Last week the sugar content had increased to between 2 and 2.4 brix. On Sunday, it had improved further to 2.8 to 3 brix which is high. At 3 brix it’ll take about 28.7 gallons of sap to make a gallon of syrup. With the improving sugar content, shorter sweeter runs will take less sap volume to make a gallon of maple syrup.

Excerpt from “Maple rule of 86”
It’s quite the fashion now to know
A fact on which to bank –
The sugar content of the sap
From trees and storage tank.

A sap hydrometer is used
Which quickly tells this tale.
It shows that trees will vary much
In sweetness in each pail.

The average figure known, you find
The syrup that it makes:
How many gallons of your sap
Each syrup gallon takes.

You ask me how to problem’s solved?
It’s easy, all you do,
Divide the Number Eight-Size*
By sugar content true.