With winter quickly melting away, the trees are just beginning to swell in preparation for spring. That can only mean one thing: time to make birch syrup.
We made birch syrup for the first time last year and tapped 10 birch trees in our yard. It was a grand experiment, and far more labor-intensive than I had imagined. Below is the process we used, as well as some notes and links to other birch syrup resources.
Birch sap is far thinner than maple sap. In fact, it takes about 100 gallons of sap to make a gallon of syrup. Birch sap begins to run in early April, so now is the time to consider harvesting.
Tools you’ll need:
- A drill and 7/16″ drill bit
- Plastic spiles (can find some here)
- Plastic 5 gallon buckets
- A shallow pan to evaporate sap (we used a roasting pan)
1. Drill holes
Sap runs up the tree around the perimeter — in fact, nearly all of the water is drawn up the tree just under the bark. If you’ve ever nicked a birch tree this time of year, you’ve seen how profusely they weep sap.
Drill holes 1 1/2 inches deep, on the north side of the tree, at a slight upward angle. Place a piece of tape on your drill bit (as shown below) to ensure proper depth.
Holes should be drilled on the north side of the trees. This prevents the buckets from heating up in the sun unnecessarily, which reduces the chances of the sap spoiling. Holes should be offset from previous years’ holes.
Find trees that have a large diameter, and are somewhere that you can easily access. Each tree can produce over a gallon a day, and with only 10 trees, we were still hauling heavy buckets of sap up and down our steep lot!
Spiles should be gently tapped into the tree. You want the spile to be firm in place so no sap can escape around the edges, but not so tight that it impedes sap flow or cracks the sap wood.
3. Place a bucket under the spile.
Some people place mesh or other material on top of the bucket to reduce the amount of bark/bugs/etc that collect in the sap. I just ran all my sap through a tea filter or cheesecloth to remove any foreign material.
4. Collect sap once a day. Filter it and simmer it.
Sap must be collected daily. Because it’s water full of nutrients, it is easily contaminated by microorganisms if left out in the sun too long.
Evaporating the sap was by far the most time-consuming part of this process. We first tried evaporating it on a camp stove, but was going through fuel canisters way too fast. Eventually, we settled on using roasting pans on the stove. Our gas bill was substantially higher the month we made syrup, the windows had to be open to release all the moisture in the house, and the stove was running 8-12 hours a day. Commercial producers use reverse osmosis to remove most of the water, then evaporate the rest.
We ended up boiling the sap until it reduced by half, then simmered it on low until we removed the rest of the moisture. We had no way to determine how much water was left in the syrup, so we simply let it simmer on low until it appeared “syrupy.” Remember, five gallons of sap only creates about a 1/2 cup of syrup.
5. Put the syrup in jars and enjoy!
Syrup is fairly shelf-stable, so we simply boiled some canning jars, warmed the syrup, and placed the syrup in the jars. We didn’t process the jars at all. We found the syrup to have a stronger taste than maple. It was very reminiscent of molasses. We used it on pancakes (and I want to incorporate some into my homemade bacon brine). However, I have a friend who look a few pints and made a fantastic birch stout.
Online source for spiles: