When the sap starts to flow (in Montana)
Maple trees (Photo by Erica Zurek for the Daily Montanan).
On a mild spring day in 2015, David Knudson had an uncharacteristic amount of time on his hands. He had recently left his job as a cheese maker at Lifeline Creamery to stay home with his children.
Standing in his yard and looking up at the trees in front of his house, Knudson felt a spark of inspiration and realized what his next big project was going to be.
He would make maple syrup.
The following day, he bought supplies to tap the trees in his residential Missoula neighborhood.
It was past the maple sugaring season, so he held on to the newly purchased equipment and tapped trees for the first time in 2016.
“I’ve always been this overly zealous entrepreneur about making things out of unwanted resources, and that’s what mushroomed my maple syrup project. It happened unintentionally. I have a lot of trees, and I made a crapload of syrup.” Knudson said.
However, climate change is having a direct impact on maple syrup production, because tree tapping is dependent on weather conditions.
Inconsistent starts to the sugaring season due to warming temperatures and changes in freeze and thaw cycles are threatening traditional maple syrup producers and requiring the industry to adapt.
Tapping maple trees is one of the oldest food traditions in North America. Native Americans began the practice of making maple syrup from sap long before Europeans arrived.
According to the USDA’s Maple Syrup Production report, 3.42 million gallons were produced in the United States in 2021.
Knudson is the only licensed maple syrup producer in Montana. He operates Montana MapleWorks with a cottage food license, which, according to the Montana Department of Public Health & Human Services, allows certain food items to be produced in a home kitchen and sold directly to the consumer.
Knudson refers to himself as an agriculturalist. While living in Santa Rosa, California, he attended New College of California, which no longer exists, and studied ecological agriculture, learning how to live a more sustainable lifestyle in changing times.
He has always been interested in botany and trees and the connection with food and its systems.
Knudson spent some time working in a brewery in San Francisco and liked knowing which farms produced the hops they used and that East Bay dairy farmers were using the mash from the brewery’s spent grain.
After a stint working on an organic farm in Missouri, Knudson moved to Missoula, where his mom lived, and started working for Lifeline Creamery in Victor, Montana.
During the summer months, Knudson stays busy growing table grapes on land he purchased in the Bitterroot Valley. Around Valentine’s Day, before the trees begin to bud, the maple sugaring season begins.
“That’s when the temperature swing starts happening and the trees start flowing.” Knudson said.
In Montana’s Bitterroot Valley, the Daly Mansion sits between the Bitterroot and Sapphire Mountain ranges in the town of Hamilton. Nearly 10,000 people who visit the mansion and its grounds annually are welcomed by sugar maples lining the long front lane that leads to the historic home.
Volunteers keep the mansion running, and the sale of maple syrup from its trees is a significant springtime fundraiser.
Bob Gibson lives about five miles from the mansion. He grew up in Los Angeles, retired 13 years ago from pasta sauce giant, Ragu, and moved from the hot Central Valley of California where tomatoes are grown, to the much colder climate of Western Montana.
Giving to the community is important to Gibson, and he decided one of the best places he could spend his time was at the Daly Mansion.
According to Gibson, about 25 years ago, two men, Fred and Doc, got together and started messing around with maple trees at the mansion. They worked out a system of tapping trees and boiling the sap into syrup.
Years later, after Fred and Doc tired of making syrup, Gibson and four others learned their techniques and formed a maple syrup group, which Gibson co-chairs. They have been at it for 11 seasons now.
“So, we learned about tapping trees and the old fashioned way of making maple syrup, which is drilling a hole in the tree, putting in a plastic spile, collecting sap with buckets, boiling the hell out of it until it is down to a syrup and then putting it in quart jars.” Gibson said.
A lot of labor goes into making maple syrup, and a cyclical weather pattern above and below 32 degrees determines the appropriate time to tap a dormant tree.
Gibson looks for a 10-day window in late spring when the nights are cold enough that the flies haven’t started to come out and the daytime sun warms the valley.
Once the weather cooperates, Gibson and his partners spring into action. “If the trees are running really strong, we can fill a five gallon bucket up in two days.” Gibson said.
A strong flow requires Gibson and his maple syrup group to boil the sap three times a week. For every 40 gallons of sap they collect, they can expect to get one gallon of syrup.
On a good year, the Daly Mansion sells anywhere from 11 to 15 gallons of maple syrup in sterilized quart jars.
But the last few years haven’t been great for sales. Two out of the last three seasons have not produced any syrup.
The weather never provided the cyclical pattern needed for consistent sap flow. Cold spells followed by a warming trend didn’t allow for the perfect rhythm that Gibson relies on.
“Our weather patterns have absolutely changed. And, if it gets any worse, I don’t know that we’ll be able to make maple syrup. The trees will survive and still leaf out onto the streets but they won’t have that concentrated sap flow that we have to have.” Gibson said.
To deal with the impact of a changing climate, large-scale commercial maple syrup producers are implementing new technologies and sap collection methods.
At the Proctor Maple Research Center, a field station at the University of Vermont, scientists are researching how to increase sap yields and exploring sustainable practices and tree health.
Timothy D. Perkins, professor and director of the Proctor Maple Research Center, grew up sugaring with his father, grandfather and uncle.
Historical records from the region show that the sugaring season has shifted earlier over time. People used to make maple syrup until the month of May. Now, the season ends in early to mid-April.
The Research Center has responded to a changing climate by finding ways to expand the duration of the season using new technologies.
“The transition from winter to summer was occurring more quickly. Once we understood this, we found ways to keep tapholes viable for longer periods. The solution for now is to use a really good vacuum system and really good sanitation of the taphole and tubing.” Perkins said.
The vacuum does not cause any internal or external damage to the tree.
“We are getting triple what traditional techniques would use,” Perkins said.
It allows the tree to give considerably more sap and stretches the sugaring season out by a couple of months.
In Missoula, Knudson is still sugaring the old-fashioned way, but his production has scaled up quickly. Last year he tapped 200 trees.
He uses a city map to determine which trees are privately owned, talks to landowners about tapping their trees and then processes the sap in his backyard.
Passion and gumption drive Knudson to continue tapping trees and experimenting with syrup colors and flavors. He doesn’t eat a lot of sugar but believes maple syrup has a romantic quality that is good for the soul.
Knudson loves teaching and he hopes to expose more people to the joys of maple syrup and the practice of tapping trees sustainably.
“I don’t even care from a business standpoint, I just love what I do.”
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