Birch sap, Birch Syrup or Birch water is an ancient spring tonic which can be gathered as just quickly and easily from a pruned twig as from the trunk without harming the tree.
In early Springtime many people head out to the woods to tap the rising sap from Birch trees (Betula pubescens, Betula pendula,) as they begin to hydrate and send sugars from the root store out to the rest of the tree. This process fuels spring growth and allows the leaves to open and begin photosynthesis.
The sap in Birch trees typically starts rising in early Spring, (late January- early April depending on spring conditions in your region) and runs for 2-3 weeks. Sometimes on the rare occasion, you may get four weeks.
Traditionally when tapping trees for sap, a bore hole is drilled into the trunk, with the well meaning but mistaken belief that by plugging the hole afterwards the tree won't be harmed – WRONG!
Respected Bushcraft experts had believed this to be the case and circulated this as fact, but recent studies of trees tapped over the last 20 years showed a large number developing decay, hollowing the trunk and snapping off at the tap wound within 12 years.
Breaking into a tree’s bark seal and drilling into the trunk causes a deep wound, making it vulnerable to fungal spores. The air in any woodland is full of decay fungi spores at all times even though we can’t see them, so it is inevitable that a drill going into the stem will open the stem up to the air, and the spores, and indeed carry spores into the wound itself. If we cut a twig rather than bore into the stem, the yield in terms of sap will be identical.
Trees are evolved to be continually browsed by animals and survive, especially sweet trees such as Birch that are loved by herbivores. Trees don't heal damage, they seal it off, so sealing off a damaged twig end far from the structural part of the main stem is easy for the tree, it is well adapted to do this.
What determines yield is the size and condition of the tree, not where you draw the sap from, so a large tree will produce the same volume of sap in a given period of time whether taken from trunk or twig.
To collect your Birch water, simply snip the end of a twig and secure a sterile bottle to it using tape or string. Leave overnight and collect your yield! Birch Sap should be clear like water and has a slightly sweet, delicious taste. Once extracted keep the birch water refrigerated. You can drink it fresh or reduce it down to make a syrup.
In the UK you can also try this sap extraction technique with Maple and Sycamore trees.
So it's simple, if the yield is identical, then there is no benefit to tapping the main trunk of your Birch tree, and it will probably kill it within the decade. Tapping the twigs is the only choice if you really care about the tree.
WILD FOOD & FORAGE DAYS
If you'd like to discover more of nature's harvest, why not join one of our wild food and forage day workshops which run in Spring and Autumn.