This year, we decided to embark on a new adventure learning to tap birch trees and make birch syrup. The new house came with a small birch forest and we were all home all the time so we decided to add a new element to our “urban homesteading”: Birch Syrup.
Now, before you start this process, let me start with two disclaimers:
DISCLAIMER #1: You should not do this for the cost savings. Making birch syrup is not at all cost-effective. You can buy 8 oz. of birch syrup from the professionals for $29. Because birch syrup has a 100:1 ratio (meaning it takes 100 gallons of sap to make 1 gallon of syrup – compared to maple which has a 40:1 ratio), it takes a lot more work.
DISCLAIMER #2: Birch syrup, if boiled, tastes bitter and molasses-y. This can still be used as a delicious glaze on things, but is not pancake syrup. If someone says they hate birch syrup, they likely haven’t tried it cooked correctly. Because birch sap consists of a different kind of sugar than maple, you can’t just boil it. In fact, if the sap goes above 180, it will burn. This means you can’t actually boil it at all.
The combination of the 100:1 ratio and the fact it can’t actually be boiled means you really can’t make a good birch syrup without a reverse osmosis system. This allows you to pull out around half of the water from the sap without heat at all. We DIY’d our reverse osmosis system using the instructions provided by Souly Rested (if anyone deserves the Amazon affiliate commission for providing useful content, it is them with this post).
How to Tap Your Birch Trees
Being new to this, I attended webinars on the topic and read every available resource on the internet. Ultimately, what you need to know was written up by the professionals in their article: Tapping a Birch Tree. Be sure to check if your birch trees are at least 25″ in circumference. Smaller than that can hurt the tree. If you’re doing it as a family like we did, I recommend the Molly of Denali episode called: Sap Season. Molly of Denali is a FABULOUS cartoon all about life in Alaska and they do a great job explaining how to do it.
When to Tap Your Birch Trees
This was the hardest part. We wanted to start right away! And I checked every single day and saw people reporting that sap was flowing in Fairbanks and the Mat-su Valley and our trees were dry! We even saw someone on the other side of Anchorage getting sap three full days before we did! But, based on my research and our experience this year, we learned it’s best to set up 2 test taps in different locations in your yard when things are getting close. How do you know they’re getting close? Well, I’ve heard many things: after you’ve seen 4 mosquitoes, when the base of the trees are out of the snow; but mainly, it ends up being after about 3 nights above freezing and 3 days above 50 degrees F. All of our trees starting flowing at the exact same time. So, our two test taps started dripping within an hour of one another. It was a notably late year according to the experts; the sap started flowing April 23. Next year we’ll set the test taps and stop freaking out so much.
How to Process the Birch Sap
Birch sap can go bad quickly, so it has to be collected daily and stored somewhere cool (we buried our collection barrel in a mountain of snow before the snow melted and we collected all the sap in the barrel each morning). If you’re doing more than 15-20 trees, you’ll also likely have to start processing the sap each day so you can keep up.
Our process was:
- Collect all sap in the barrel each morning
- Run the reverse osmosis system – the pure water output would be piped to buckets, the sap runoff would be sent back into the barrel so it could run continually until we turned it off. Generally, we would keep it running until we’d pulled out about half the water (ie: the water in the buckets equaled about what was left in the barrel).
- Pour the remaining sap from the barrel into our steam table pan on the camping stove
- Heat the sap until about 160 degrees F (we had a meat thermometer probe attached to the side of the pan)
- Turn on the bubbler at 160 – This was something we hadn’t initially planned on, but it turns out, it takes FOREVER for the water to evaporate out of the sap without boiling it. So Mr. T built a bubbler contraption out of CPVC pipe with holes drilled in the bottom attached to an air mattress pump we got at Target. This blew bubbles into the sap to simulate boiling at a low temperature and helped the water evaporate WAY faster.
- Bubble the sap around 170 until the liquid level is 1-2 inches deep (too low for the bubbler to help). Don’t let it go above 180! (We set an alarm on our thermometer so we could run out and turn the heat down before that happened.)
- At this point, if we had the previous day’s sap we had completed to this point in the fridge, we would combine the two and then let it bubble again until it was 1-2″ deep.
- Use the refractometer to check brix levels. Birch syrup is done at 67 Brix (same as Maple). It took several combined days to get up to 40+ and then we had to complete it to 67 in a turkey roasting pan on the stove (again, don’t let it get above 180 degrees!).
- Strain through coffee filters (it will take several filters as the sediment that’s created when heating the sap will clog it quickly) while it’s hot and put immediately into jars and seal.
Other Birch Syrup Info
- Birch syrup is very distinct. It tastes nothing like maple and is kind of hard to describe. It’s sweet and woodsy.
- Early run birch syrup is lighter in both color and flavor than late-run birch syrup. The sap starts to yellow as the sap flows, resulting in the change in color.
- Taps should be pulled out when the sap turns cloudy (usually when the buds burst into leaves on the tree).
- Holes should be left unplugged and if you tap the same tree the next year, it should be at least 6″ away from this year’s hole.
How Much Does Birch Syrup Cost?
- Components for the Reverse Osmosis system: $388.47
- 30 Taps: $70.51
- Sap Buckets & Food Grade Garbage Can to use as Collection Barrel:$207.10
- Tubing and clamps: $54.06
- CPVC pipe for bubbler: $14.70
- Blower for bubbler: $12.19
- Steam Table Pan for cooking into syrup: $30.76
- Adorable 8oz syrup bottles: $28.99
- 2 Propane Tanks: Free – A friend had a few extras and gave them to us
- Propane: $52.70
- Coleman Camping Stove: Free – I got a bonus at work in the form of a Cabela’s gift card that just covered the camping stove.
- Refractometer: $23.99
TOTAL COST: $883.47
After about 17 days and nearly 200 gallons of sap, we ended up with 2 gallons of syrup. So…
TOTAL COST PER GALLON: $441.74 – remember how I said you should just buy it from the professionals?! Well it actually turns out that if you’re buying it for $30/8 oz from them, it would cost you $480 (lucky for you, they also sell it in 32 oz jugs for just $105).
Hopefully next year, we can bring the cost down significantly since much of the cost this year was one-time purchases. Overall, we really loved the process. It was fun to do each day as a family, and it comes at the perfect time (the 2 weeks before the trees get leaves, so we’re all antsy for spring and needing something to do until it comes!). Also, we’ve got the neighbors on board and we may be doing a street-wide birch tapping blitz next year! I’ll let you know how it goes. 😉
lakesidemom
Thanks so much for sharing the link to our RO system! I’m so glad it’s been working well for you! –Michelle
MaggieBanks
Thanks for taking the time to write it all up! We wouldn’t have tapped our birch trees without those instructions.
Brittney Maguire
How long does it take to put the sap through the RO system? Or rather how much sap can it process say per hour?
MaggieBanks
We run it on a loop until we get about a third to half of the water out of our daily haul, so it’s hard to say how long it takes to go through it, but I can tell you that it usually takes about 3 hours to get fifteen gallons of water out of 40ish gallons of sap.
Tawcan
You have one heck of a system set up there Maggie. So next time we do visit Fairbanks, can we try some of this birtch syrup?
MaggieBanks
If you come to Anchorage, I will feed you salmon dinner and give you a taste of birch syrup. 😉
onjwagner
Do not miss the Kahiltna Birchworks.
onjwagner
I built a Souly Rested RO just to do black birch syrup in at 2,500′ elevation in NE TN. Really strange sap situation. Did not run anything but a light brown froth till about 3rd week in March. Sap then was .3 Brix, next week it was .5 Brix, next it was 1.0 Brix and next the tap had run dry. I kept one batch (after ROing) under 200 F in an electric skillet and it was WAY better than just boiled down which was like tar. Most appropriate comment was the “just boiled” would be good in bar-b-que sauce. Can’t wait to try bubbling air through sap next winter! Thanks so much for posting this.
MaggieBanks
I bet it would be good in BBQ sauce!
Dan Burbank
I made birch syrup 2 years ago up here in North Central New Hampshire in the southern White Mountains. It is every bit as hard to do as previous post had said. I also do maple syrup and there is absolutely no comparison the birch I would describe as molasses with hints of blueberries it is nothing that you want on your pancakes although I do like it on vanilla ice cream. I made it the same way as I do my maple syrup but more like 57 brix vs 66 brix on maple syrup. It was very time consuming because I used buckets vs tubing that I use for my sugar bush mainly because the birch is located on level ground so it would flow so I used 5 gallon buckets. I ended up with about 1 gallon which I thought was cool considering there’s only 5,000 gallons produced annually worldwide yes worldwide! Would I do it again yes it was very interesting and challenging most people will spit it out upon tasting it it really needs to be used as a glaze for salmon, trout or a glaze for pork.
MaggieBanks
It’s very good mixed with whipped cream on pancakes.