Birch

Betula pendula

Family: Betulaceae Part used: Leaves, bark (betulin), sap

Key Compounds

• Betulin
• Betulinic acid
• Hyperoside
• Quercetin 3-galactoside
• Myricitrin
• Luteolin
• Apigenin
• Chlorogenic acid
• Caffeic acid
• Methyl salicylate
• Pentacyclic triterpenes
• Saponins

Traditional Use

• Urinary tract and kidney support — German Commission E approved birch leaf for irrigation therapy (diuresis and urinary tract flushing) for urinary tract inflammation and kidney gravel prevention; the flavonoids (hyperoside, myricitrin) and saponins produce diuretic effects without electrolyte depletion; used with adequate fluid intake (2L/day) as per Commission E recommendation
• Spring detoxification tonic — birch sap drunk in early spring as a traditional tonic across Scandinavia (Finland: mahla, koivun mahla; Sweden: björksav; Russia: берёзовый сок berezoviy sok); sap collected by tapping in early spring before leaf emergence; contains fructose, glucose, various minerals, and small amounts of bioactive compounds; the tradition is at least 1,000 years old in Scandinavia and Russia
• Anti-inflammatory — methyl salicylate (related to aspirin's active compound) and flavonoids provide mild anti-inflammatory effects; traditional application for joint pain and skin inflammation; the salicylate content is lower than in willow bark but contributes to the anti-inflammatory profile
• Skin health — birch bark extract (betulin and betulinic acid) used in cosmetics and topical preparations for eczema and dry skin; betulin has anti-inflammatory properties relevant to skin; birch tar (*Betula* tar, distinctly different from coal tar) is used in dermatological preparations for psoriasis and seborrhoeic dermatitis
• Finnish sauna tradition — birch whisks (vihta or vasta) used in Finnish sauna practice; bundles of young birch branches soaked and used to lightly beat the skin during sauna; the tradition promotes circulation, the volatile compounds in the birch leaves contribute aromatic and mild anti-inflammatory effects through steam; this is national cultural heritage practice, not primarily a medicinal application

In early spring, before the leaves emerge, birch trees run with sap.

The pressure builds as the tree begins pushing nutrients toward the expanding buds. If you tap the bark, the sap drips out. Several litres a day, per tree, for two to four weeks. Then the leaves open and the flow stops for the year. This window is what Scandinavian and Russian tradition has been harvesting for at least a thousand years. The sap is drunk fresh, fermented into wine, or preserved. It tastes slightly sweet and clean, faintly of the forest.

The white bark is white because of betulin — the first terpene ever isolated from a plant (1788). The same compound that makes birch visible across a bare landscape.

Meet the plant

A pioneer tree — among the first to colonise bare ground after fire or clearance. White papery bark with black basal markings, weeping branchlets, small triangular-to-diamond-shaped leaves. Common throughout temperate and boreal Eurasia and North America, from sea level to the subalpine zone.

The German Commission E approval

German Commission E approved birch leaf for urinary tract irrigation therapy — the same framework as goldenrod and dandelion. Flavonoids (hyperoside, quercetin 3-galactoside, myricitrin) and saponins produce diuretic effects without electrolyte loss. Used with at least 2 litres of water daily to flush the urinary tract mechanically.

The Commission E indication: inflammatory diseases of the lower urinary tract and prevention of kidney gravel. The same combination of diuretic increase and mild anti-inflammatory activity that makes the urinary herb category useful.

The sap tradition

Birch sap is consumed across Finland, Sweden, Norway, Russia, Poland, and the Baltic states as a spring tonic. The timing matters: early spring, before the leaves emerge, when the sap pressure is highest. Fresh sap ferments within 2–4 days; it is drunk immediately or preserved.

The composition: approximately 1% glucose and fructose, minerals (manganese, magnesium, calcium), trace amino acids, and small amounts of the same flavonoids found in the leaves. The traditional tonic interpretation — spring renewal, post-winter restoration — corresponds to the diuretic and mineral-replenishing properties of the sap.

Commercial birch sap beverages are available in Nordic countries and are growing as an export product.

Betulin and betulinic acid

The white compound coating the outer birch bark is betulin — 22–30% of dry outer bark weight. Betulin was isolated in 1788 by T.E. Lowitz, making it historically significant as the first terpene isolated from a plant.

Betulinic acid (derived from betulin by oxidation) has attracted pharmacological interest:

• Anti-tumor activity in cancer cell lines (melanoma and other cancers)
• Antiretroviral activity (anti-HIV in cell and animal models)
• Anti-inflammatory properties

These are laboratory findings. Oral bioavailability of betulin compounds is poor. The compounds are being investigated for pharmaceutical development, but neither betulin nor betulinic acid has established clinical applications as supplements. The laboratory evidence is real; the clinical application is investigational.

What people actually do with it

Leaf infusion (diuretic/urinary): 2–3 teaspoons dried birch leaf per cup, steeped 15 minutes. 3 cups daily with 2 litres of water. Spring to early summer is traditional timing; the German Commission E protocol does not restrict to season but the spring tonic tradition reinforces the timing.

Birch sap: Drunk fresh in spring (primary Scandinavian and Russian consumption). Available commercially as bottled birch water. No standardisation; mineral content variable.

Birch leaf tincture: 2–4 mL, 3 times daily, in water.

Birch bark preparations (topical): Birch bark extract cream or ointment for eczema or dry skin conditions. Products specify betulin content. Not for internal use.

Could you grow this yourself?

Birch grows readily in temperate climates from seed or transplant. B. pendula (silver birch) is drought-tolerant once established; B. pubescens (downy birch) prefers wetter soil. Both grow quickly for a tree species. For sap collection, a mature tree (>15 cm trunk diameter) is needed; tapping is done in early spring with appropriate care to not damage the tree.

Birch (白樺) in Japan

白樺 (shirakaба, Betula platyphylla var. japonica) is the Japanese white birch — a different species from European B. pendula but closely related and sharing the distinctive white bark. It grows in cool mountain regions, most prominently in Hokkaido.

The shirakaба became culturally significant in Japan through the Shirakaba literary movement (白樺派) — a group of Taisho-era writers (1910s–1920s) who took their name from the white birch forests of Shiga Kogen in Nagano Prefecture. The movement included authors such as Mushanokoji Saneatsu and Shiga Naoya, and represented a humanist, individualist literary philosophy. The white birch tree became symbolically associated with this idealism — purity, northern isolation, modern Japanese literature.

Birch leaf tea and birch sap products are available in Japanese natural health markets, following the European tradition. The cultural resonance of 白樺 makes birch products particularly appreciated in the Hokkaido premium foods market.

Things you’re probably wondering

Is birch the same as the Ogham letter beith? The first letter of the Old Irish Ogham alphabet is beith (birch). In the medieval Irish tree calendar tradition, birch represented new beginnings — which reflects its ecological role as the first coloniser of cleared or burned land. The symbolic meaning is ecologically accurate: birch does appear first.

Can birch sap be fermented? Yes. Birch sap ferments naturally within days, producing a mildly alcoholic drink. Traditional birch wine or birch kvass are produced deliberately in Scandinavian and Eastern European folk tradition. Commercial birch sap is pasteurised to prevent fermentation.

Botanical details

The full compound list

See Also

• Goldenrod — urinary irrigation herb; German Commission E for same indication; often combined with birch
• Nettle — spring tonic and urinary herb; traditional combination with birch
• Dandelion — diuretic with potassium-replenishing properties; complementary urinary herb

References

• Blumenthal, M. et al. (2000). Herbal Medicine: Expanded Commission E Monographs. American Botanical Council. (German Commission E birch leaf monograph)
• Yogeeswari, P. & Sriram, D. (2005). Betulinic acid and its derivatives: a review on their biological properties. Current Medicinal Chemistry, 12(6), 657–666.
• Grieve, M. (1931). A Modern Herbal. Dover. (Sap and bark uses documented)
• Moerman, D.E. (2009). Native American Medicinal Plants. Timber Press.