Sweet_season

Jeff Green | Mar 16, 2006

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Sweet season soon

Commentary by GrayMerriam

The days are getting longer and soon we will get some of those sunny days with 1 to 2 degree temperatures (38 to 39 F) that will trigger the flow of sap. A new set of spiles will be tapped into big hard maples, fires will be lit under the boiling pans and lots of late nights will be needed to mind the thickening syrup.

Ontario and Quebec maple product producers dominate their industry. They have a classical renewable resource industry that is, at the same time: a winning economic competitor, moving ahead technologically, and conserving and enhancing our landscapes. A healthy stand of sugar maple trees contributes to a healthy landscape and makes that landscape an important resource for society and the province.

“The [maple] producers of Ontario and Quebec are such aggressive marketers that they are filling the growing demand in the United States virtually single-handedly” , says the Director of the Cornell Maple Program. This Maple Program is receiving huge financial and staff injections in response to the excellent Canadian industry.

Although there is still some mystery in how sap is actually moved to the top of tall trees, the basics of sap and syrup production by sugar maples are traditional knowledge. But there are many important details that require new knowledge. A most fundamental issue is that quality maple syrup depends on raising the concentration of one sugar, sucrose, from a concentration in the sap of about 2% to a syrup concentration of 66%. The first increase in sucrose can now be done by recent technology called ‘reverse osmosis’ which will elevate the sucrose about 5-fold to around 12%. But a lot of water still must be ‘boiled off’ to get to 66%. Modern sugar shacks catch all that steam and reuse the heat trapped in it.

In all the processes from sap dripping from spiles to sap in plastic tubes to sap in tanks to final syrup, it is essential to prevent the breakdown of sucrose into its two constituent sugars, fructose and glucose. Preventing the formation of glucose in the sap is vital because when boiled, glucose turns brown and bad-tasting. Keep the sugar as sucrose and this does not happen. You get Number 1, good-tasting, good-looking syrup.

The breakdown of sap into brown and bitter glucose is largely the work of bacteria and fungi. So just a spike of too-warm weather during the sap run will increase the populations of fungi and bacteria and can ruin the syrup produced.

Learning how to prevent this microbiological sucrose breakdown is one of the major research projects underway at the Cornell University Sugar Maple Field Station just outside Lake Placid , New York . Other research there includes learning the genetic basis for maples that produce especially sweet sap, as high as 12%. They also have learned how to propagate those ‘sweet trees’ from cuttings that will flower and produce seed in the year they are rooted instead of after 20 years, the normal time in the wild.

In another maple research station they are perfecting sugar bush management methods. For example, cutting smaller, less-productive trees to ‘release’ the surrounding highly productive trees from shading and nutrient competition will increase production from the big trees that have been ‘released’ but will lose the production from any trees that are cut. How much will it increase the flow from a ‘producer’ tree if you cut several surrounding, smaller, less-productive trees that are shading the big producer and how much will you lose in production from those smaller trees that you cut? What is the rule of thumb for managing a sugar bush?

This maple program, just south of us, is going to produce new knowledge that Canadian producers could use as they work to keep their hard-won leading position in the maple market in the U.S. That Lake Placid research station is not far away. When you visit, hide your ‘eh?’ or they will think you are an industrial spy.