bigleaf maple tree on Vancouver Island Did you know bigleaf maples (Acer macrophyllum) are the largest and most common maple trees on Vancouver Island?

This “big daddy” of the Pacific Northwest boasts a height of 40 to 80 feet tall, a canopy that extends as far as 50 feet and sap with a sugar concentration fit for syrup production.

The leaves of the tree create sugar through photosynthesis. The sugar is stored in the roots and sapwood of the tree. Trees use sugar to grow buds, leaves, branches, sapwood and to heal wounds. The sapwood is near the outside of the tree and is the conduit for moving sap.

In honour of the recent Bigleaf Maple Syrup Festival, followed closely by pancake Tuesday, we’ve put together some information on how to tap bigleaf maples.

Thanks to Gary and Katherine Backlund authors of Bigleaf Sugaring: Tapping the western maple for sharing the information.

When is the Best Time to Tap Your Maple Sap?

On Vancouver Island, tapping is best done between November and early March (once all the leaves haven fallen off the tree and before the buds open the following spring). Sap flows are normally sweetest in January and February. On the west coast, a good rule of thumb is that sap often flows a day before or after a change in the weather.

How Do You Know Which Trees to Tap?

An ideal tree has a wide-open crown, a trunk diameter between 4 and 18 inches and somewhat smooth bark. Although large diameter trees are desirable in the east, in the west large old gnarled hobbit maples seldom give much sap unless you can tap a sucker stem. When a maple tree is cut down, it sends up many new shoots (coppices) from the stump. These work well for tapping as they have a large established root system and you can use a big bucket to collect from several stems.

How to Tap Your Bigleaf Maple?

spiles for tapping sap to make maple syrup

Taps are called spiles (left image). Most commercial spiles are designed for a 7/16-inch hole. Ideally, you want to tap at a convenient height. Some folks recommend you tap on the sunny side of the tree directly under a large branch. Others suggest you work around the tree and get slightly higher with each new hole (assuming you tap the same tree year after year).

Tap holes are more productive if drilled on days when the sap is flowing. The hole is drilled 2 to 2.5 inches deep at a slight upward angle. If you drill too deep you may hit heartwood and decay.

When drilling the hole you should use a twist bit as opposed to a flat (speed) bit because a flat bit can clog the opening of the hole and reduce sap flow.

shows depth to place spile to tap sap and make maple syrup

Once the hole is drilled, drive the spile in place gently with a hammer to prevent leakage. Some spiles have a small hole that can clog up and stop the flow. You may want to pull the spile after several weeks to make sure no wood or sugar is plugging the spile.

You may also find that your holes dry up before you want them too. Usually, you’ll need to drill a new hole nearby after about 4 to 5 weeks.

Once the spile is removed it will take about a year for the hole to fill over with new wood.

How to Best Collect and Handle Sap?

milk jug collecting sap from a bigleaf maple tree on Vancouver Island

It’s nice to know some solutions are simple. Four-litre plastic milk jugs work well for collecting sap. The first step is to cut a hole where the milk jug tapers for the neck. Next, simply slip the jug over the spile. (right image)

using an oil jug to collect sap from bigleaf maple trees For highly productive trees, or multiple stems, you can connect spiles with tubing to a large bucket instead of using milk jugs.

Cooking oil buckets (16 litres in size and often  available for free from restaurants) work well for collecting and handling sap. (left image)

Remember: Your collection system should prevent rainwater and insects from mixing with the sap.

The best idea is to collect sap at least every three days. Most of the run occurs during the warmest part of the day, but sometimes trees flow all night long.

Once collected, store your sap in a cool place. Because sap contains sugar and yeast it can easily sour. Ideally, you should boil your sap down every few days.

How Can You Use Your Sap?

Because sap is only available three or four months of the year, making syrup is a great way to condense and preserve this wonderful product for the other eight months.

Sap (also called maple water) contains amino acids, vitamins and many trace minerals. While turning sap into syrup is the most common use, you can also use sap in place of water when you’re making tea, coffee, cooking rice, soup, stew, bread and other beverages.

How to Boil Down Your Sap to Make Syrup?

Sap is about 98% water. Boiling sap causes the water to evaporate which reduces the sap to syrup. At 2% sugar it will take about 43 litres of sap to make one litre of syrup.

If you’re boiling-down your sap indoors, you’ll have about 42 litres of steam to deal with. Using wood or propane heat outdoors is preferred. Stainless steel or cast iron flat bottom pans or large diameter kettles are best. Sap is considered syrup at 66.5% sugar.

Here are the steps to follow to boil-down your sap into syrup:

  1. Fill your pan with sap and heat to a rolling boil (some people filter the sap first).
  2. Skim any foam that appears off the top.
  3. As levels drop, add additional sap (slowly in order not to kill the boil).
  4. Taste occasionally for sweetness. Sap can burn easily when it’s close to done, so when it tastes quite sweet, bring the pan indoors to finish carefully on the stove.
  5. You can judge doneness by taste alone or by measuring temperature.
  6. To measure temperature: boil some water and measure the boiling temperature with a candy thermometer (the boiling temperature of water changes daily with atmospherics conditions). Water turns to gas at boiling so you can only reach approx. 212 degrees Fahrenheit and no hotter. Your syrup will be 66.7% sugar when its boiling temperature reaches 7 degrees Fahrenheit higher than the temperature of boiling water. It’s the sugar in the syrup that allows you to reach the higher temperature.

Important: CAUTION!

Your sap/syrup will be a very hot liquid, so be careful!! Things move fast at the end and you don’t want to accidentally burn or boil-over and ruin all your hard work.

It’s best to finish off a large quantity of syrup rather than a small one. You can evaporate your sap until it’s about 50% sugar, freeze it and store until you have at least a litre to finish.

How to Preserve and Store Your Syrup?

Strain the hot finished syrup through a felt or milk filter to remove the sugar sand (coffee filters also work, but not as well). If you decide not to strain the liquid, the sugar sand will settle to the bottom of the jars. No big deal. It’s a matter of preference.

The sap can then be poured into hot sterile jars and sealed or frozen. The sugar content preserves the syrup. If the sugar content is too low, the syrup can spoil. Syrup that grows mold can be filtered and re-boiled with no damage to the flavour.

Happy sap tapping!

A big PFLA thanks to Gary Backlund for sharing the information with us and a hearty congratulations on another successful Bigleaf Maple Syrup Festival!

Visit the PFLA Facebook page to check out some archived photos of the Bigleaf Maple Syrup Festival from a few years ago.