Wiktionary
n. the sap extracted from a birch tree
Wikipedia
Birch sap or birch water is the sap directly tapped from birch trees, Betula alba (white birch), Betula pendula (silver birch), Betula lenta, Betula papyrifera, and Betula fontinalis.
Birch sap is collected only at the break of winter and spring when the sap moves intensively. When fresh, it is a clear and uncoloured liquid, very similar to water, often slightly sweet with a slightly silky texture. After two to three days, the sap starts fermenting and the taste becomes more acidic. Birch sap may be consumed both fresh and naturally fermented.
Birch sap is a traditional beverage in boreal and hemiboreal regions of the northern hemisphere as well as parts of northern China.
Usage examples of "birch sap".
I've known him to use grains, fruits, honey, birch sap, even some roots, and turn out a drink that most people like, and he makes it for almost every occasion when people get together.
There was some of fermented brew made from birch sap, but Ayla decided she drink it, and she was pleased to see a woman coming around Iff hot herb tea into cups for those who wanted it.
Some areas of Scandinavia are suitable for collecting birch sap, another form of sugar from sap, but only some.
Ma Lomas made wine from elderflowers, elderberries, nettles, dandelions, birch sap, rhubarb, gooseberries and whinberries.