The Sweet Reward of Tapping into Bigleaf Maples

While no small labor, the depth of flavor in bigleaf maple syrup is worth the effort for hobbyists and possibly commercial producers.


Nate Daniel, executive director of Great Peninsula Conservancy, considers himself a syrup hobbyist. His introduction to tapping maple trees came the year he worked at a University of Rhode Island extension farm. Inside one of the barns he found a dusty old crate with an evaporator pan and all the equipment inside to produce syrup. He cleaned it and set it up at what’s called a sugarbush — the area where tree tapping takes place.

“They were real sugar maples and the sap was running in February as it has for a couple hundred years in the northeast,” Daniel said. “It was super fun and produced a significant amount of syrup.”

He said it’s fun to sit around and feed logs into the fire and smell the syrup start to condense. “It’s a relaxing thing to do on a Saturday. It’s a winter hobby.”

It takes about 40 gallons of sugar maple tree sap to produce a single gallon of syrup in places like Rhode Island and Vermont. When a forester from the Mount Baker area told Daniel about the future of bigleaf maple syrup here, it piqued his interest. Different species, but the same idea.

It takes over twice the amount of sap from bigleaf maples, about 86 gallons of sap to produce a gallon of syrup. Sap contains somewhere between 97 and 99% water, but also minerals, vitamins, amino acids and sugar, mostly sucrose.

Local conservationist Kit Ellis was intrigued as well. She has 194 wooded acres in conservation, so she and Daniel gave it a shot last year and learned a lot. The goal was to produce one gallon of syrup, a modest goal they thought. But Ellis said it never got cold enough that winter. Without the cold freeze and thaw process, the sap doesn’t run very much. They collected maybe 10 gallons total of sap.

“I made the mistake of boiling that down on my stovetop,” Daniel said. “The result was small and steamed up my whole house. This year we will try a different method.”

The University of Washington and Washington State University Extension Forestry teamed up with a small grant from the USDA to explore the feasibility of commercial tapping of indigenous bigleaf maples.

Patrick Shults, WSU Extension forester described the processes in a Jan. 12 webinar, “Introduction to Bigleaf Maple Sugaring.”

Shults operates a sugarbush demonstration at the Meyer’s Point Environmental Field Station in Olympia, set up as part of a University of Washington research project.

The sap season for Bigleaf maples begins when temperatures go below freezing, anywhere from November through March depending on elevation, and requires keeping a close eye on weather forecasts.

Freezing temperatures create negative pressure inside the tree. That pressure draws water up through the roots into the xylem, or sapwood, to the upper part of the tree where it stays until warmer temperatures thaw out the sap, which runs back down through the tree picking up sugars and minerals along the way.

“Because there is a higher relative pressure inside the tree at that point, it actually pushes the sap out through a tap hole that we create and that’s how we go about collecting sap,” Shults said. “This is a feature that is pretty unique to maples and a handful of other species.”

Shults said people often ask if tapping hurts the tree. “Technically yes. But it is minimal, if we’re doing it correctly.” He likened it to giving blood.

“Nobody likes being poked with a needle and having blood drawn but you heal up and your body makes more blood. It’s the same with the tree and similar to a pruning wound.”

Bigleaf maples suitable for tapping are greater than 10 inches in diameter at the base. Sick, dying or stressed trees as well as large old growth trees or trees with heart rot should be avoided. Other site factors include grade and water table.

Tapping basics include strategic drilling of a 2-inch deep hole and immediately inserting a metal or plastic tap using a hammer or rubber mallet until hearing a “thud.” Proper placement of taps is essential and multi-stemmed clumps of trees can work well. The number of taps per tree depends on the diameter of the tree, ranging from one to three taps. Keeping future taps in mind, one cannot tap the same spot twice. Trees begin to heal immediately and may be tapped two or three times in a season.

There are several types of sap collection systems for hobbyists, each with pros and cons, including buckets or bags directly from the spile, or tubing carrying the sap to a bucket on the ground. Another is making use of gravity to create a natural vacuum and connecting taps to plastic tubing to drain into a collection tank.

Clean equipment is essential. To avoid bacteria growth, sap should be processed immediately. Processing means evaporating all the water from the sap; there are many options from homemade to commercial at varying costs. Wood fired evaporators are best at the hobby scale.

The resulting syrup can be finished on the stove, measuring with a brix gauge to achieve a 66-69 brix. Once filtered, the syrup can last a year in the fridge, and several years canned in glass jars or in the freezer.