This past week has been very busy in many maple producing regions across the province.  Earliest regions are finished for the year, while mid and late-season areas were still in full production.  It has been a good production season so far for many producers.

Although winter started off with odd mild weather that made many people wonder about the maple syrup season, it was a reminder that we need to be patient, not jump to conclusions on the productivity of the season until start-to-finish has actually happened. With each maple syrup season, we never know the final crop yield or syrup quality until bud growth dictates that it is finished.  We aren’t done yet.

Once buds on maple trees have started to show advanced growth and buddy off-flavours in sap appear, the return of freezing nighttime and thawing daytime temperatures or fresh snow cover in the sugar bush won’t reverse the trees back to producing good quality sap.

Buddy off-flavour means the chemistry of the sap has changed to signal tree growth to begin.  In a few weeks, the maple trees will be growing a leafy canopy, new sapwood, flowers may form a seed crop, and in the latter part of summer and early fall, trees will be manufacturing the 2018 crop of maple sugar.  Unseen in the soil, thousands of tiny roots will be absorbing nutrients and moisture as they extend through warming soil.

Sap and syrup update

Early southwestern regions and Niagara are now finished sap harvest and syrup processing for the 2017 season. Buddy off-flavour sap is now present in hard maples as the buds have swollen to begin flowering and vegetative growth.  Estimates indicate that the final syrup crop yield reached average to above average quantities, 1.1 to 1.6 litres syrup per tap, where modern vacuum systems are operating.

In Niagara, taps on soft maple trees were pulled from trees back in mid-February due to concern of advanced bud growth and off-flavours.  Fortunately, hard maples remained dormant to provide a final crop yield of 1.2 to 1.4 litres of syrup per tap, and representation of all colour grades.

Grey / Bruce Counties and central areas:

• Flavour – Good, rich and stronger flavours now evident
• Colour – medium, amber to dark (new system)
• Sap % sugar – low:  1.8% – 1.9%; high:  2.1% – 2.3%; roadside:  3%
• Volume (so far this season) – low range:  57% – 70% (no vacuum);  high range:  130% – 153%
• Bud movement – buds are still tight; some movement in the far south of the local
• Volume of sap flow this past week – light to medium

Haliburton, Kawartha and Uxbridge regions – producers have been busy this past week, the syrup yield ranges from 50 to 90 percent of a crop, tending towards lighter grades of syrup, having fine maple flavour.  Maple buds are still dormant in areas further north where snow cover is still present, more good sap runs are anticipated.  Maple syrup producers in central regions should keep a close watch on bud development over the coming week as temperatures are expected to remain above freezing as the week progresses.

Northern late areas are early to mid-way through the sap harvest season. Excellent sap flow conditions are forecast for the coming weekend in northern regions over to Sault Ste. Marie.

The post-season cleanup

Maple syrup producers in early areas of the province are finished sap harvest for the 2017 season.  The task of cleaning everything up is a big job.  Cleaning and sanitizing sap lines, evaporator pans and other food contact surfaces is far less a burden where the work is completed as soon as possible following sap harvest and syrup processing is finished.

Where sugary food residue is left too long on surfaces, it can harden into a cement-like layer, becoming very difficult to remove. Maple equipment dealers have cleaning and sanitizing products that are designed specifically for maple equipment.

Cleaning and sanitizing sap tubing

During the latter part of sap harvest, the inner surface of sap collection tubing becomes covered in a bio-film layer of sticky sweet residue, bacteria, yeast and mould.  If left to sit as spring temperatures begin to warm, the collection of organisms inside the tubing can quickly fill the inner tube walls with mould.

It is important to flush the sap tubing with potable water to remove the sugary sap as soon as possible after the season.  Once clean, many producers currently use isopropyl alcohol  as an effective sap line sanitizer.  Isopropyl alcohol is Federally registered for use in Canada as a sap tube sanitizer.  Maple researchers in Quebec have been conducting trials on the effectiveness of isopropyl alcohol and its safe use in maple sap collection tubing.  The results have contributed to the current recommendations of use.

A back-pack tank to carry isopropyl alcohol 70% dilution, and dosing gun allow precision application of 15 millilitres per spile.

It is very important to know how isopropyl alcohol should be used in sap tubing.  The objective is to allow gaseous vapour of isopropyl alcohol to fill the tubing to sanitize the inner surface of mould organisms.  Avoid loading the tubing with liquid as this is an over-usage of isopropyl alcohol.

Follow the label directions found on the container of isopropyl alcohol and obtain a copy of the guide produced by ACER in Quebec on proper application techniques for best results.