The past week summary
In southern areas this past week, large volumes of clear sap ran early in the week from hard maples and soft maples with no buddy off-flavours detected yet. Sap sugar concentration has trended downward as would be expected during the latter half of the processing season. Soft maple: 1.5 ⁰Brix, hard maple: 1.6 to 1.8 ⁰Brix. In central areas, sap sugar ranged widely from 1.7 to 2.4 ⁰Brix.
Syrup colour is Golden and Amber with excellent maple flavour and high quality. There are average and above average amounts of sugar sand but no reports of difficulties with filtering syrup.
The syrup crop in earliest areas ranged from 50 to 90 percent in southwestern Ontario, producers have achieved 1 litre of syrup per tap now, anticipating a few more good sap runs with the next thaw. Soft maples in sugar bushes are showing advanced bud swell and will open with the next warm period, while open yard trees are now in bloom where soft maple sap is buddy and off-flavour. Buds on sugar maples are also swelling but should produce good sap the next thaw in earliest southern areas.
Central areas report 10 to 50 percent of a syrup crop so far having excellent quality and maple flavour. Buds on soft and hard maples are still dormant in central mid-season areas with swelling and development visible now.
Producers in northern regions have been frustrated by frozen conditions and more very cold conditions are still in the forecast for next week. Deep cold night-time freezing will require several days to thaw the trees after warmer weather returns. Snow levels in sugar bushes will help prevent bud development for several weeks yet. Sap harvest and syrup processing will likely proceed well into April in northern areas.
Wind damage in the southwest
High winds that occurred in southwestern areas on March 8 caused significant limb breakage and damage to sap tubing in affected sugar bushes. The freeze up that is expected to continue well into the coming week will allow time for producers to clear limbs and make repairs to tubing, hopefully before the next sap run.
Sugar bushes that have been well-managed with good thinning and forest health maintenance had far less wind damage to trees and sap tubing, compared to sugar bushes that have had less focus on good management practices. Branches snapped from tree tops allowed producers to check the stage of bud development at the canopy top, which are not normally accessible.
Sap flow forecast
We are in for a cold week ahead. Cold wintry weather is predicted for the coming week. Maple trees will freeze again stopping sap flow. Although frozen trees will mean no sap runs for a few days, on the positive side the cold will also stop further bud development to keep sap quality good for making syrup when thawing conditions return. As a result, producers may see a lightening of colour in the next batch of syrup.
Reducing greenhouse gas emissions
Manufacturers of maple syrup evaporators began implementing new engineering for high-efficiency energy use years ago, in advance of any regulated requirements. Driven by need, maple syrup producers were most interested in reducing the costs associated with fuel to boil sap to syrup, and reduce the long hours spent supervising the boiling process.
Except for hobby evaporators, most modern commercial evaporators that are fired by oil, traditional firewood or wood pellets operate at high-efficiency and produce low greenhouse gas emissions. Modern evaporators provide faster processing times compared to evaporators in use just a few decades ago.
Most recently, fully automated electric evaporators are available that can operate with the push of a button and can be monitored remotely with confidence. Research engineers are also investigating magnetic induction as a potential future method of processing maple syrup. Electric evaporators have zero carbon emissions, at the sugar bush.
Conventional reverse osmosis (RO) technology provides a significant advantage for syrup production by removing 75 to 80 percent of the water from raw sap before boiling. Pre-concentrating the sap using RO drastically reduces the quantity of fuel needed to process maple syrup. The availability of small portable reverse osmosis units has recently enabled many producers having fewer taps (500 to 2000 taps) to reduce fuel costs and reduce greenhouse gas emissions at the farm by pre-concentrating the sap.
In summary, advancements in efficiency with low greenhouse gas emissions, energy cost reductions, options for using renewable fuel, electric processing and reverse osmosis have made the commercial production of pure maple syrup environmentally advanced and admired.