Weather Conditions for Sap Flow

The brief warm spell that has moved into southern regions of the province mid-week may have maple producers preparing trees for tapping.   Thawing temperatures during the day with freezing temperatures at night occurring for several consecutive days may induce sap flow in sugar maple trees in early areas of the province.   The risk to tapping this early in the year however, will risk tap holes drying up before the good sap flows that are expected to occur in late February and March.  Tap hole sap flow tends to have a limited life-expectancy of 4 to 6 weeks, and maple producers should plan their tapping carefully in order to optimize the total sap collection as the season progresses.  

In previous years, many maple producers have collected a significant amount of their maple syrup crop by catching early sap flows.   Be very careful to avoid drilling and tapping maple trees while the wood is frozen.  The wood should be at least -5 ¢ªC or higher to prevent healthy wood from splitting when spouts are set into the freshly drilled tap holes.   Each producer should make their own judgment on when tapping should commence, especially where close attention to the health of each sugar bush is monitored during the spring, summer and fall.  Most maple producers tend to delay tapping their maple trees until late February and early March to ensure tap holes continue to run sap through to the end of the normal sap flow season.  

Sugar Bush Health

In Ontario, sugar maple trees should be in a good healthy condition for the 2009 tapping season.  Plenty of soil moisture over the 2008 summer growing season should have prepared maple trees with a good supply of stored sugar.   Localized areas of the province that experienced heavy defoliation in maple trees last summer by gypsy moth or tent caterpillar may have sugar maple trees in stressed condition for this 2009 tapping season and maple producers in these areas may consider following reduced tapping guidelines.   Some areas of southwestern Ontario, such as Essex and Kent Counties, did experience extended drought conditions during 2008 and sugar maple trees in these droughty areas would benefit from reduced tapping or even no tapping for the 2009 sap flow season.

Maple producers can take advantage of several upcoming Woodlot Owner Workshops to learn leading-edge technology of woodlot management.  The Lindsay Woodlot Conference is February 20.   The Grey/Bruce Woodlot conference will be held March 28 in Elmwood.  The Ontario Woodlot Owners Association annual conference is March 28 in Acton.  Contact MNR Stewardship Coordinators for meeting details.

Proper Syrup Density

For the 2009 tapping season, maple syrup producers should pay very close attention to proper calibration and proper use of their measurement equipment.   Survey samples of maple syrup collected from the 2008 maple syrup crop showed that too many batches of finished maple syrup were below the legal density for sale in Ontario.   

Maple syrup can only be legally offered for sale if it has reached a density of at least 66 ¢ªBrix.  To obtain this minimum density, syrup should be boiled until it reaches a temperature of 4 ¢ªC (7.1 ¢ªF) above the boiling point of water.  Therefore, minimum density maple syrup will boil continuously at 104 ¢ªC.  The only way to ensure that the legal minimum sugar density is reached is to know that thermometers, refractometers and hydrometers are calibrated properly with each batch of processed sap and syrup run.  Remember that the boiling point of water can vary with changing barometric pressure and can change significantly during the course of each day.

So again, proper calibration of all syrup measurement equipment is necessary to ensure reliable readings and quality maple syrup is produced.  A final syrup density between 66.5 and 67.5 ¢ªBrix has a more pronounced maple flavour and better texture, ideal for quality maple syrup and returning customers.

Setup

All maple collection and processing equipment that will be in direct contact with sap, syrup and value-added maple products should be cleaned and sanitized in preparation for the approaching syrup season and should be constructed of proper food-grade materials.  Where possible old equipment with lead-soldiered joints or materials manufactured of metals that aren¡¯t suited to food processing should be replaced with new equipment.

Permanent vacuum tubing systems can be installed and inspected for any air leaks that will hamper sap collection.  Wildlife such as squirrels, voles and raccoons can cause significant damage to vacuum tubing each year by chewing holes in lines.   Prepare a plan to inspect sap lines frequently during and between each sap flow event to ensure leaks are repaired as they appear.   

Drill bits used for tapping maple trees should be sharp, clean and disinfected prior to tapping maple trees and should be disinfected periodically while drilling tap holes.  Where decayed or dis-coloured wood is encounter while drilling tap holes, drill bits should be replaced with clean sterilized drill bits before proceeding with more tap drilling to ensure subsequent tap holes are not infected with micro-organisms by a contaminated drill bit.

Woodlot Safety

Working in the sugar bush has some risks to the safety of every individual.  Several prominent maple producers in Ontario have recently been very seriously injured while working in their sugar bush.   Maple producers are advised to never work alone in their sugar bush especially where chain saws are being used to clear trees or fallen limbs.  Proper safety equipment for woodlot maintenance must be worn at all times while working.  All equipment that is used for maintenance of the sugar bush should be in proper and safe working condition.  All individuals who will be using the equipment should be adequately trained and certified to use the equipment.   Cell phones or walkie-talkies are a necessity for sugar bush workers in order to summon help quickly in the event of a serious injury.

This report has been prepared by Todd Leuty, Agroforestry Specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs.