Perhaps one of the first signs of spring is the sap flowing in the maple trees. Sap runs best when the night is cold, below freezing and the days mild. With those first drops of sap dripping from the tap, maple trees can seem to wake up after a long winter
During freezing temperatures, sap flows up from the roots and as the temperature rises, sap's journey is downward and will flow out a spout when the tree is tapped. Maple syrup might even be seen as the first crop of the year in Northern Minnesota.
To the casual observer, a concentration of sap filled blue bags attached to a stand of maple trees in the woods may look like an unexpected outdoor art installation.
Lorie Shaull
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KAXE
Trees other than sugar maples can be tapped, but the sap in sugar maples has a higher concentration of sugar at about 2%, making it ideal for maple syrup.
Lorie Shaull
/
KAXE
Lorie Shaull
/
KAXE
The process of boiling down sap into syrup takes place in an evaporator. Commercial evaporators can be purchased, but there are many DIY versions out there. It’s just a way to boil down large amounts of sap into a 66% syrup concentrate.
Lorie Shaull
/
KAXE
KAXE Morning Show host Heidi Holtan and her husband Tom Cobb started maple syruping during COVID-19. The blue, sap filled bags and their red barn in the morning light create a photogenic sugar bush.
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— Bags containing maple sap and a red barn in Grand Rapids on March 31, 2025.jpg
Bags containing maple sap and a red barn in Grand Rapids on March 31, 2025.
Lorie Shaull / KAXE
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— Bags containing maple sap in the snow in Grand Rapids on April 3, 2025.jpg
Bags containing maple sap in the snow in Grand Rapids on April 3, 2025.
Lorie Shaull / KAXE
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— Tom Cobb checks the density of the maple sap with a hydrometer in Grand Rapids on April 3, 2025.jpg
Tom Cobb checks the density of the maple sap with a hydrometer in Grand Rapids on April 3, 2025.
Lorie Shaull / KAXE
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— Heidi Holtan carries bags of sap to pour into a 35 gallon container in Grand Rapids on April 3, 2025.jpg
Heidi Holtan carries bags of sap to pour into a 35 gallon container in Grand Rapids on April 3, 2025.
Lorie Shaull / KAXE
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— Closeup of a bag containing maple sap in Grand Rapids on March 29, 2025.jpg
Closeup of a bag containing maple sap in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Heidi Holtan removes a bag of sap from a maple tree in Grand Rapids on March 29, 2025.jpg
Heidi Holtan removes a bag of sap from a maple tree in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Tom Cobb tastes the maple sap as it boils down in Grand Rapids on March 29, 2025.jpg
Tom Cobb tastes the maple sap as it boils down in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Tom Cobb pours maple sap into a 35 gallon container in Grand Rapids on March 29, 2025.jpg
Tom Cobb pours maple sap into a 35 gallon container in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— A tube from a 35 gallon container attached to a reverse osmosis system in Grand Rapids on March 29, 2025.jpg
A tube from a 35 gallon container attached to a reverse osmosis system in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Jars of maple syrup in Grand Rapids on March 29, 2025.jpg
Jars of maple syrup in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
The maple trees where Phenology Coordinator Charlie Mitchell lives have been tapped for longer than Charlie has been alive. She estimates her dad likely started around 1976 but the previous property owners were running the sugarbush in the 1930s. It's possible, she says, the St. Croix Band of Ojibwe could have run a sugarbush here too.
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— Charlie Mitchell uses a sieve to skim out impurities from the maple sap in a maple syrup evaporator pan in Marine on St. Croix on April 11, 2025.jpg
Charlie Mitchell uses a sieve to skim out impurities from the maple sap in a maple syrup evaporator pan in Marine on St. Croix on April 11, 2025. Charlie notes, early in the season, the sap run is crystal clear with a hint of blue; as the season progresses, it can become more cloudy and yellow although color is highly variable between different trees.
Lorie Shaull / KAXE
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— A sap bucket hangs on a tree in Marine on St. Croix on April 11, 2025.jpg
A sap bucket hangs on a tree in Marine on St. Croix on April 11, 2025.
Lorie Shaull / KAXE
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— 02 Charlie Mitchell pours sap through a sieve that her wife, Hayley, holds in Marine on St. Croix.jpg
Charlie Mitchell pours sap through a sieve that her wife, Hayley, holds in Marine on St. Croix on April 11, 2025.
Lorie Shaull / KAXE
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— Charlie Mitchell holds a jar of maple syrup in Marine on St. Croix on April 11, 2025.jpg
Charlie Mitchell holds a jar of maple syrup in Marine on St. Croix on April 11, 2025.
Lorie Shaull / KAXE
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— 02 Charlie Mitchell holds a sap gathering bucket beside a maple syrup evaporator in Marine on St. Croix on April 11, 2025.jpg
Charlie Mitchell holds a sap gathering bucket beside a maple syrup evaporator in Marine on St. Croix on April 11, 2025.
Lorie Shaull / KAXE
On a chilly morning in late March, the Forest History Center in Grand Rapids hosted “Maple, Music & Phenology” to demonstrate the process of traditional maple syruping, complete with pancakes and coffee percolated using maple sap.
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— Mark collects a spile and bucket of maple sap from a tree during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Mark collects a spile and bucket of maple sap from a tree during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Mark and Michael guide the draft horses down a trail during the Maple, Music, & Phenology event at The Forest History Center in Grand Rapids on March 29, 2025.jpg
Mark and Michael guide draft horses, Jack and Chad, down a trail to help gather buckets of sap during the "Maple, Music, & Phenology" event at The Forest History Center in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Aaron Prudhomme, with Dale Wilson, pour maple sap into the warming pan of the evaporator at The Forest History Center in Grand Rapids on March 29, 2025_1.jpg
Aaron Prudhomme, with Dale Wilson, pour maple sap into the warming pan of the evaporator at The Forest History Center's "Maple, Music & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Aaron Prudhomme, with Dale Wilson, feeds the wood-fired maple syrup evaporator at The Forest History Center in Grand Rapids on March 29, 2025_1.jpg
Aaron Prudhomme, with Dale Wilson, feeds the wood-fired maple syrup evaporator at The Forest History Center's "Maple, Music & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Art Norton, with Aaron Prudhomme, uses a hydrometer to measure the density of maple syrup at The Forest History Center in Grand Rapids on March 29, 2025_1.jpg
Art Norton, with Aaron Prudhomme, uses a hydrometer to measure the density of maple sap in the evaporator at The Forest History Center's "Maple, Music & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Art Norton uses a hydrometer to measure the density of the maple syrup at The Forest History Center in Grand Rapids on March 29, 2025.jpg
Art Norton uses a hydrometer to measure the density, or specific gravity, of maple sap in the evaporator at The Forest History Center's "Maple, Music & Phenology" event in Grand Rapids on March 29, 2025. The sugar percentage of the sap is measured in degrees Brix, where one degree Brix equals 1% sugar content; the standard density for maple syrup is 66.9 Brix.
Lorie Shaull / KAXE
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— Art Norton checks the temperature of boiling maple sap during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Art Norton checks the temperature of boiling maple sap during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025. He explained, the ideal temperature is greater than 212 at about 217 degrees Fahrenheit.
Lorie Shaull / KAXE
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— Kate Langley pours out maple syrup for pancakes during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Kate Langley pours maple syrup for pancakes during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Kate Langley makes pancakes on a wood burning stove during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Kate Langley makes pancakes on a wood burning stove during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Melanie McCoy pulls a spile out of a tree during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Melanie McCoy pulls a spile connected to tubing out of a tree during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Mark holds a recently removed spile from a tree during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Mark holds a recently removed spile from a tree during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— John Beltman plays accordion during the Maple, Music, & Phenology event at The Forest History Center in Grand Rapids on March 29, 2025_1.jpg
John Beltman plays accordion during the "Maple, Music, & Phenology" event at The Forest History Center in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Alanta Will and Lillian Sheppard of Grand Rapids dance during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Alanta Will and Lillian Sheppard of Grand Rapids dance during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— John Beltman plays accordion, as others sing along, during the Maple, Music, & Phenology event at The Forest History Center in Grand Rapids on March 29, 2025.jpg
John Beltman plays accordion, as others sing along, during the "Maple, Music, & Phenology" event at The Forest History Center in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Maple sap coffee percolates on a fire during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Maple sap coffee percolates on a fire during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— John Beltman holds a cup of freshly percolated maple sap coffee during The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
John Beltman holds a cup of freshly percolated maple sap coffee during The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Skip's Sugar Bush sign and ice at The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Ice hangs from Skip's Sugar Bush sign at The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
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— Ice on branches at The Forest History Center's Maple, Music, & Phenology event in Grand Rapids on March 29, 2025.jpg
Ice on branches at The Forest History Center's "Maple, Music, & Phenology" event in Grand Rapids on March 29, 2025.
Lorie Shaull / KAXE
