While tapping maples was discovered in the new world, birch trees have been tapped by Nordic peoples for millennia. Birch sap is drunk straight as a health tonic, and it’s also made into birch beer, birch kvass and birch syrup.
I first tasted birch syrup as a sample at our local Vermont farmer’s market. The farmer warned me that it’s not like maple syrup, and you wouldn’t use it on pancakes.
It’s described as being “fruity, spicy, and sometimes reminiscent of molasses or licorice in flavor.” It’s for making spicy-sweet things, like birch syrup roasted carrots or birch syrup sweetened spice cake.
I’ll admit, it did have a bit of spice to it, but I’m still happy with it on my pancakes.
We’ve tapped maples for years, but this is the first year we tapped birch trees. We’re also experimenting with tapping linden trees and ironwood trees. There are lots of different trees you can tap for syrup, dozens in fact.
When to Tap Birch Trees
The sap flow for birch trees is after maples have finished. Maples require freezing nights and warm days to cause the sap to run.
According to Farming the Woods, one of my very favorite permaculture books, Birches begin producing sap when both days and nights are above freezing. Along with above freezing nights, the daytime temperatures need to be consistently above 50 degrees, which usually happens in Mid to Late April in Vermont.
When this happens, the maples stop producing and you can switch all your equipment over from tapping maple trees to birches. This is convenient for maple producers since they can use the same equipment to extend the season. You don’t have to choose between the two.
It’s tricky for gardeners though, because while there’s not much to do during maple season, there’s plenty to do once things warm up enough for birches to start flowing.
How to Make Birch Syrup
The thing about birch syrup is that it takes a lot of work to make it.
Birches have much less sugar in their sap than maple trees, and while it takes 40 to 50 gallons of maple sap to make one gallon of maple syrup, it takes somewhere between 110 and 200 gallons of birch sap. Farmers are paid back for that extra fuel and boil time, and birch syrup can cost as much as $400 per gallon.
Most people buy it in tiny bottles and use it sparingly.
To make birch syrup, start by tapping birch trees. Any species of birch will do, but it’s said that yellow birches produce sap with the highest levels of antioxidants.
Birch trees need to be at least 8 inches in diameter before they can be tapped, but preferably larger. For maples, they recommend 10 to 12 inches in diameter.
Equipment for Tapping Birch Trees:
- Portable Drill (we use this one)
- 5/16” or 7/16 drill bit (depending on the size of your taps)
- Tree Taps (metal or plastic)
- Syrup buckets or plastic bags
- Some way to cook the sap
You can find a complete tapping kit for maples or birches here.
As the sap begins to run, gather it daily and store it somewhere cool, preferably refrigerated, until you have time to boil. If you don’t keep it cold, it’ll begin to ferment on its own. That’s probably why it was made into fermented beverages in the past, because before refrigeration there was just no stopping it.
Just like with maples, you don’t necessarily need an evaporator to cook birch syrup. There are plenty of ways to make syrup without an evaporator.
A turkey fryer or woodstove works well, or you can rig up a backyard evaporator with steam table pans and cinder blocks. Don’t use anything aluminum, as the birch sap can corrode aluminum.
Regardless of what you use, you’re going to be at it for a long time, so make sure you’re comfortable. Grab a beer and some lawn chairs to enjoy the spring weather as you keep an eye on it.
Birch syrup contains fructose, which is easier to burn than the glucose in maple syrup. It also finishes at a different temperature.
Maple syrup finishes at 7.5 degrees above the boiling point of water. We’re at about 1000 feet above sea level, so that means water boils at around 210 degrees (as opposed to 212 F at sea level). We finish our maple syrup at 217.5 degrees.
Birch syrup finishes somewhere around 225 degrees at sea level or 13 degrees above the boiling point of water. We’ll have to cook it to 223 degrees at 1000 feet elevation. If you have a hydrometer, it should be 66 to 67 Brix.
When the syrup is finished, it can be canned for long-term preservation using the same techniques that you use for canning maple syrup.
Once the leaves begin to appear, it’s time to pull the tap. At this point, the sap will change to be cloudy and sour tasting.
If you’re looking for more specifics and technical details on tapping birches, check out The Sugarmaker’s Companion: An Integrated Approach to Producing Syrup from Maple, Birch and Walnut Trees.
How to Use Birch Syrup
So they say that it’s “not for pancakes,” but I think it depends on your tastes. Most people pour corn syrup on pancakes and don’t give it a second thought, and I’d say that stuff’s not for pancakes.
I’ll take a bit of spice along with my sweet, and I’m happy to pour it on my pancakes. Besides pancakes, it looks great as a topping for this nordic oatmeal.
Similarly, on the sweet side of things, I’d imagine this birch syrup ice cream is tasty, combining a bit of spice and bitterness with a sweet creaminess. The natural molasses flavor likely comes out strong in these birch sap chocolate chip cookies.
This birch syrup pie is basically a birch sweetened egg custard baked into a crust and it looks like a great way to showcase the flavor of birch syrup without much else to distract you. Similarly, it’s front and center in these birch syrup pecan squares.
Using Birch Sap (without Boiling for Syrup)
We are making our own birch syrup, but we’re also planning on using the birch sap in other traditional ways. While birch syrup is becoming more popular for home use these days, historically the sap was used rather than investing all that energy to boil it down into syrup.
The simplest way to use it is to simply drink it straight. The tree filters water naturally through its tissues and adds a bit of sweetness and minerals. One company sells it bottled and markets it as a natural electrolyte beverage like coconut water.
It’s delicious. It tastes just like cream soda to me, but without all the corn syrup sweetness you find in a traditional soda. All the flavor, but just a hint of sweet. It’s only 25 calories for the whole can (compared with 40 calories for maple sap seltzer), so just enough sweet to wake up your tongue, but not enough to overpower the other flavors.
Beyond drinking it straight, it’s often fermented because it’ll naturally ferment on its own without refrigeration. Traditional birch beer contained just that: birch. Birch beer generally includes both birch twigs and sap, along with some kind of sweetener, often sugar or honey.
Once you’ve made birch beer, it’s tasty on its own, or you can make it into a fancy birch beer cocktail.
Birch sap wine is only slightly different, using grape juice concentrate or cane sugar and lemon to add additional sweetness. I’m hoping to try a small batch this spring made with birch sap and birch syrup to double down on the birch-y goodness.
In Russia, birch sap was used to make a traditional fermented drink called birch kvass. A bit of birch sap was mixed with black bread, honey, barley and currant leaves for tannins. It’s a quick 3 to 4-day ferment, just long enough to make it fizzy.
Birch sap is still used medicinally in many countries in Scandinavia and Eastern Europe.
MEDICINAL PROPERTIES OF BIRCH SAP
Birch sap is traditionally used to detoxify the body and to cleanse the liver and kidneys. It’s been used to treat gout, kidney stones and scurvy, and is also promoted as a nutritional supplement for newborns and young children.
The book Backyard Medicine discusses the benefits of birch sap, noting that “Birch sap, birch water, or blood, had a folk reputation for breaking kidney or bladder stone and treating skin conditions and rheumatic diseases. It can be drunk in spring as a refreshing and cleansing tonic, clearing the sluggishness of winter from the system. The fermented sap also makes birch wine and country beers and spirits.”
Yellow birch sap, in particular, is known to have high levels of antioxidants and is sought after as a health tonic.