Betula pendula Roth

A large mature Betula pendula subsp. pendula in Staverton Park in eastern Suffolk, UK (August 2023). Image John Grimshaw.

subsp. mandshurica (Regel) Ashburner & McAll.

Betula pendula subsp. mandshurica represents the easternmost arm of the Betula pendula aggregate, occurring in a vast arc stretching from east of Lake Baikal through eastern Siberia, China and Japan to western Ontario in Canada. In the Asian part of this range, subsp. mandshurica is the common low-altitude white birch, not usually ascending into the mountains (this role filled instead by B. ermanii), whereas in western North America it constitutes the tree-line birch. It is most readily distinguished from the other Betula pendula subspecies by the presence of conspicuous hair tufts in the vein axils on the underside of the leaves, which lack of the blue-green colouration so typical of the other two subspecies and have a single order of toothing. From a distance, the tree can be recognised by the large, coarse leaves and stiff twigs, and by the absence of corky breaks in the white bark near the base of the trunk. In the vicinity of Lake Baikal it intergrades with subsp. pendula, and in northern China with subsp. szechuanica.

In Manchuria and northeast China these birches, conspicuously white-stemmed, are abundant in the cold, dry continental climate. They may be seen invading open habitats on light soils, equivalent to the heathland of western Europe (the trans-Siberian railway passes through at least one such area between Chita and Khabarovsk). In the country to the north of the Manchurian frontier, the trees are plentiful, forming a simple mix with Larix. They are also common in the north-eastern provinces of China. According to Wang (1961) they clothe the lower slopes of the mountains such as the Hsingan Range, where sturdy, wind-blasted montane Betula pendula subsp. mandshurica may be seen at higher elevations and up to the tree line; further west in the mountains of Jehol and Chahar in inner Mongolia, and Shanxi they frequently occur mixed with the Eurasian aspen Populus tremula. Further west, towards the drier grassland regions, birch and aspen groves are found only on the northern slopes of the isolated mountain ranges.

The Asian White Birch was first brought to Europe as seed and herbarium specimens from Japan. Being obviously different from European Betula pendula, these plants were named Betula japonica by Siebold in 1830 – illegitimately since Thunberg had already used the name for the Japanese alder, Alnus japonica (Thunb.) Steud. The basionym of the subspecies is Betula alba subsp. mandshurica, described by Edward Regel (1865) from Manchurian specimens collected by Friedrich Schmidt at Olga Bay, southeast Manchuria (now Primorsky Krai). A succession of other collections from far eastern Asia, now treated as synonyms, were described as species during the early decades of the twentieth century: Betula grandifolia from the Lena-Kolyma area (1905), B. platyphylla from Dahuria, east of Lake Baikal (1911), B. ajanensis from the Aldoma River basin (1921), and B. cajanderi from the Lena river (1929) and B. tauschii (1930). The exploration of Alaska led to the description of B. alaskana by Sargent in 1901 – realising that the name had already been used, in 1922 he redescribed it as B. neoalaskana. Bean (1914) included an entry for Betula alaskana (said to have been introduced to cultivation in 1905).

In Flora of China, Li & Skvortsov (1999) recognised two species, Betula pendula and B. platyphylla, where Betula pendula represents the species in northern Xinjiang west of the Altai, and B. platyphylla the birches from Mongolia east of the Altai and into western and north-eastern China. In the printed version of the Flora, Skvortsov expressly disagreed with the editorial decision that B. platyphylla be recognised as distinct from B. pendula, and considered the two synonymous. Jansson (1962) recognised a var. platyphylla within B. verrucosa (= B. pendula) found in Outer Mongolia, distinct from what he recognised as Betula mandshurica in northeastern China, but McAllister and Ashburner (2013) consider the two taxa to intergrade, and not worthy of distinguishing at species level, if at all.

Subsp. mandshurica is not very commonly cultivated and only trees of well-documented provenance are likely to be correctly identified – Japanese trees are still widely referred to as Betula platyphylla, B. platyphylla var. japonica, B. japonica or even B. tauschii. Henry reported that three 6–7.5 m specimens of B. verrucosa var. japonica growing at Kew – ‘narrowly pyramidal in habit and very ornamental on account of the beautiful white bark’ – had been raised from Japanese seed received from Sargent in 1891 under the erroneous name B. ulmifolia (in Elwes & Henry 1906–1913). Generally coarser in foliage than subsp. pendula, subsp. mandshurica is probably a less attractive tree, except perhaps for autumn colour. On the other hand, the early leafing seen in many wild collections when planted in the milder parts of western Europe is very welcome for the brilliant translucency of the young leaves when other trees are still bare, the shoots and leaves being damaged by only the severest air-frosts. Collections from Japan and the Kurile Islands are growing well at Ness and Stone Lane Gardens.

A small group of Betula pendula subsp. mandshurica (of uncertain provenance) is the first birch into leaf at Mill House Arboretum, Shropshire, UK (27 March 2023). Image Tom Christian.

A particularly white-barked example of Betula pendula subsp. mandshurica, Kuril Islands provenance (Stone Lane Gardens, Devon; 3 December 2022). Image Julian Sutton.

A seed-raised group of Betula pendula subsp. mandshurica dating from 1984, Hokkaido provenance (Stone Lane Gardens, Devon, UK; 3 December 2022). Image Julian Sutton.

Bark of Betula pendula subsp. mandshurica, Hokkaido provenance (Stone Lane Gardens, Devon; 3 December 2022). Image Julian Sutton.

A group grown as 'Betula japonica' at Thenford House, Northamptonshire, UK (May 2009). Image Owen Johnson.

Betula pendula subsp. mandshurica of western North American provenance at the Royal Botanic Garden Edinburgh, UK, where it is always among the first birches into leaf (19510072*A, grown as Betula neoalaskana) (7 April 2025). Image Tom Christian.

A stand of Betula pendula subsp. mandshurica growing on lower elevations of of Changbai Shan, Jilin, China. The red autumn foliage of Cornus alba is in the understory (late September 1997). Image Paul W. Meyer.

Slender trunks of Betula pendula subsp. mandshurica frame the view across the Yalu River looking into North Korea near Changbai Shan, Jilin, China (late September 1997). Image Paul W. Meyer.

subsp. pendula

Loved for its grace and beauty, the European Silver Birch, Betula pendula subsp. pendula is immediately recognisable from a distance by its thin flexible twigs, which hang down vertically, particularly on older trees, and by its white bark that splits into dark corky ridges and cubes at the base of the trunk; at closer quarters the diagnosis is confirmed by the roughly triangular, double-toothed leaves. Though some other species (e.g. Betula nigra) may weep to some extent, no other birch has branchlets which droop so elegantly. This characteristic shows as a fine and beautiful tracery in winter, while in summer the foliage moves easily, each individual long-stalked leaf fluttering readily in the slightest wind. Valley populations in Scotland, particularly in the east, and in Norway, are especially magnificent, and fine trees of great beauty and grace are abundant across the north European plain, in southern Sweden and across the Baltic States.

Betula pendula subsp. pendula plays a dynamic role in the landscape, as an early component of seral successions. Seedlings will readily invade gaps in the woods, or indeed any open ground, and young trees crowd abandoned industrial sites, quarries, and old railway yards. For this reason, the tree is ubiquitous on northern European heathland – Bagshot Heath in Britain, the Veluw in Holland and Luneburg Heath in Germany – where the poor, sandy soils are wide open for invasion by birch, particularly following fire. It will also colonise limestone, including chalk soils (Atkinson 1992), although it is less common on these than on more acid soils, perhaps because of competition from the wider range of woody species able to colonise soils of a high pH. The Silver Birch is not universally loved: ecologists condemn it as a destroyer of heathland as it shades out the heather (Calluna vulgaris) and replaces the lowland heath by birch forest, even though the heaths are man-made habitats created from woodland by cutting, burning, and grazing. In theory the birch in turn should be shaded out – in classic succession – by pine and oak, but this seldom happens: pines and oaks are usually kept at bay by human disturbance, grazing, burning or felling and birch continues to dominate. Where birch replaces heathland it also increases soil fertility so that it may be difficult to re-establish heathland on the site (Mitchell et al. 1997, 2007). And in Britain and other countries where conifers are the main timber trees, foresters find the tree a nuisance, since its branches whip around in the wind and damage other trees.

Although the white birches of Sweden were well known to him, Linnaeus in Species Plantarum (1753) did not distinguish between the Weeping Birch, Betula pendula Roth. and the Downy Birch, B. pubescens Ehrh., the two taxa being formally disentangled only as late as 1904 by Engler (as B. verrucosa and B. pubescens). The name used by Linnaeus for the two species, B. alba, could never be typified unambiguously, leading to confusion, and is now a rejected name (Govaerts 1996; Nicolson 1999). The name Betula verrucosa has long been used, in Europe especially, for the Weeping Birch – indeed it is particularly apt, derived from the Latin verruca (‘wart’), in reference to the rough glands on the most vigorous shoots and youngest twigs which characterise almost all populations of this species; the older name B. pendula, however, is correct, though less apposite since only the European populations have the characteristic weeping branches. Hybrids are reported between B. pendula and B. pubescens.

The leaves of Betula pendula subsp. pendula are easy to recognise, with their combination of triangular or deltoid shape, acuminate apex and double toothing. Their bluish-green colour and high gloss could only be confused with that of subsp. szechuanica, but in that subspecies the leaves are usually coarser, more leathery and usually with only a single order of toothing. With the possible exception of some Iberian populations, the leaves of subsp. pendula lack the elegant, really long points of B. populifolia, and nowhere approach the dull yellow-green, twisted coarseness and leathery quality seen in subsp. mandshurica.

In terms of bark, subsp. pendula alone appears to develop the dark corky ridges and cubes at the base of the trunk, though Ashburner and McAllister (2013) note the existence of some European populations in which the bark is smooth and white to the base: these have been distinguished as var. lapponica (from Scandinavia) and var. aetnensis (from Sicily), though the latter does develop corky fissures after about thirty years. Otherwise, the absence of corkiness is a good character for distinguishing typical subsp. mandshurica and subsp. szechuanica – indeed the disappearance of fissured bark in Siberia is one obvious character change where populations of subsp. pendula merge into those of subsp. mandshurica. In the eastern European form described as Betula obscura the bark is dark grey or blackish brown.

In the south of Europe, many of the populations of Betula pendula still weep, some exaggeratedly, such as the beautiful trees in the valleys of the Massif des Écrins in France and the Gran Paradiso in Italy, in which the smooth whiteness of the bark extends into the crowns of the trees. The finest of these alpine birches are the somewhat twisted individuals in the highest valleys near their upper limit, magnificent when seen in brilliant young leaf against melting snow in May or even June. Trees at high elevations in Corsica are very similar, as (apparently) are those in Macedonia and Bulgaria. The most southerly birches in Europe are the renowned populations on Mt Etna in Sicily, splendidly white against the black of new lava flows in spring and early summer, or in the gold of autumn, so much that local people come especially to see ‘le betulle’ at these times. Farthest south of all are the white birches of the El Rif mountains of Morocco, described as Betula fontqueri Rothm., based on a minor difference in the sweep of the lateral lobes of the bract scales – this name has also been applied (at subspecific rank) to populations in central Spain and the mountains of the southeastern part of the peninsula (Moreno & Peinado 1990). These mediterranean birches represent remnant populations that have survived the glacial maxima in southern mountain redoubts (Carrion 2002; Huntley & Birks 1983; Willis, Rudner & Sümergi 2000). Recent molecular evidence suggests that they did not contribute to the post-glacial recolonisation of northern Europe (Palmé & Vendramin 2002; Palmé et al. 2003; Maliouchenko et al. 2007). Though they have long been isolated from one another, probably during both glacials and interglacials, none of these southern populations – including ‘Betula aetnensis’ and ‘B. fontqueri’ – seem to have evolved sufficiently to merit taxonomic recognition.

Betula pendula subsp. pendula has always been a favourite in the landscape, planted frequently in gardens despite the consequent difficulty in growing anything beneath trees whose shallow roots rob the surface soil of moisture. Most individuals are rewardingly graceful, but some are more so than others, and when raising a batch of trees intended for the garden, it is always a good idea to harvest seed from the best. As one of the most ozone-tolerant woody plants of central Europe (OECD 2003), the species as a whole thrives in urban situations. It grows in any well-drained soil, and is relatively fast-growing, reaching 4 m or more after ten years. One negative character is that its fallen twigs can be untidy, especially after a winter storm.

Several cultivars have been selected from unusual or aberrant variants, found either in the wild or in rows of nursery seedlings. Propagation is straightforward by grafting or semi-ripe cuttings taken in July. Among the ornamental traits selected are coloured (purple, yellow), variegated or highly dissected leaves – covered in detail in the separate article on cultivars. The most obvious feature to exaggerate in subsp. pendula is the weeping habit, achieved spectacularly in the selection ‘Tristis’ (possibly synonymous with ‘Elegans’), on which thin swaying branchlets hang like curtains. This clone exhibits the fine winter tracery of subsp. pendula even better than usual and its trunk is smooth to the base.

There is a remarkable concentration of cut-leaved and reduced-leaved forms of subsp. pendula in Scandinavia, where they occur naturally as aberrant individuals (Hylander 1957). Many of these form trees of normal stature, and the dissected leaves add to their elegance. A significant number have been named and propagated, famously ‘Dalecarlica’. These cut-leaved varieties may be homozygous for a recessive gene, as seedlings of one of the best known, the cultivar ‘Crispa’, revert to the type form (the same phenomenon is seen in Scandinavia in Alnus incana and A. glutinosa). Reduced forms such as ‘Arbuscula’, small-leaved and finely-toothed, may be natural hybrids with the dwarf birch Betula nana. Again, it is interesting that these exaggerated leaf-forms appear to be concentrated in Norway, Sweden and Finland, not having been reported from populations of the other subspecies.

A grove of Betula pendula subsp. pendula growing in Windsor Great Park, UK. Image Paul W. Meyer.

A good young Betula pendula subsp. pendula in autumn colour at St Leonards-on-Sea, East Sussex, UK (8 December 2013). Image Owen Johnson.

A large mature Betula pendula subsp. pendula in Staverton Park in eastern Suffolk, UK (August 2023). Image John Grimshaw.

Alastair Gunn gives scale to Betula pendula subsp. pendula in Staverton Park in eastern Suffolk, UK (August 2023). Image John Grimshaw.

An enormous Betula pendula subsp. pendula in Staverton Park in eastern Suffolk, UK (August 2023). Image John Grimshaw.

A wild Betula pendula subsp. pendula 27 m tall at Foxhill House, Cheshire on a northwest-facing sandstone bank on which birches of all kinds grow exceptionally well (12 May 2023). Image Owen Johnson.

A gnarled, aging specimen of Betula pendula subsp. pendula growing in the Brecon Beacons National Park, Wales, UK (28 September 2022). Image Paul W. Meyer.

A grove of Betula pendula subsp. pendula growing in Windsor Great Park, UK. Image Paul W. Meyer.

Betula pendula subsp. pendula in glorious autumn colour (Yorkshire Arboretum, UK; November 2019). Image John Grimshaw.

A large Betula pendula subsp. pendula, 22 m tall and of exceptional form, at Trews Weir Reach, Exeter, Devon, UK (5 May 2013). Image Owen Johnson.

The yellow early summer foliage of Betula pendula 'Golden Cloud' (Writtle College, Essex, UK; 17 June 2017). Image Owen Johnson.

A particularly shapely Betula pendula subsp. pendula glowing in evening sunlight on Blackheath Common, Surrey, UK (November 2018). Image Aidan Champion.

An extraordinary extreme variant of Betula pendula subsp. pendula. This is a spontaneous seedling from 'Trost's Dwarf' with very finely dissected leaves that appeared at the Elisabeth C. Miller Botanical Garden, Seattle (June 2023). Image John Grimshaw.

subsp. szechuanica (C.K.Schneid.) Ashburner & McAll.

This must be the birch with the whitest bark of all – truly chalk-white in maturity, though with suggestions of buff or pale orange when younger. The Chinese White Birch is well known in many arboreta and botanic gardens, forming a stocky, somewhat untidy tree with deep blue-green leathery leaves and extraordinarily pure white bark, which sheds copious white dust that ‘comes off on the hands like old whitewash’ (Alan Mitchell, quoted in Bean 1976).

Betula pendula subsp. szechuanica appears to be confined to southwest China and southeast Tibet, and was frequently observed and collected from Tibet, northwest Yunnan and Sichuan in the early years of the twentieth century by Wilson, Rock and Forrest. Ecologically it seems to be a filler in gaps in the mixed secondary forest of those regions. It also forms subalpine montane forest in the drier inner ranges of southeast Tibet, though apparently not on the moister main Himalayan range. To judge from photographs taken by Charles Howick in southeastern Tibet, it is frequent in some valleys, and would presumably invade any suitable open area.

The subspecies was first described as a variety of Betula japonica in 1917, later transferred to a variety of B. platyphylla, and later again raised to specific rank as B. szechuanica. It is here named Betula pendula subsp. szechuanica. Intermediates occur between this generally glabrous southern subspecies, and the northern subspecies mandshurica, in which axillary tufts of hairs are common. Rock 14718 from southwest Kansu province and Purdom 371 from Shensi (Shaanxi) province in north China have some axillary hairs and are geographically intermediate between the Mongolian populations and the Tibetan and south west Chinese populations of Yunnan and Sichuan. More surprising was to find some axillary hairs on Forrest 22520 from the Lijiang in northwest Yunnan, well within the core area of typical Betula szechuanica. This finding muddies one of the possible distinguishing characteristics for B. szechuanica and links these southwestern Chinese populations with those further north. This blurring of the picture is par for the course in birch taxonomy.

Betula pendula subsp. szechuanica is readily identified by the very white, dusty bark, the large, leathery, dark, blue-green leaves, rather sparse on long shoots with long internodes, and the usually single-toothed leaf-margin and usual absence of axillary hair tufts on the leaf underside. The scales of the male catkins are sometimes humped, so the dormant catkins of some trees feel more or less ‘knobbly’. The general habit of older trees is characteristically stocky and spreading.

Numerous collections of this subspecies have been made, and have grown well and are now widely distributed in gardens and arboreta. There seem to be no problems with early leafing or failure to mature the summer’s growth. Occasionally there may be die-back due to damage from a late frost. There is a curious lack of autumn colour, certainly in cultivated trees in England, where the leaves remain persistently green then shrivel, turn brown and drop off (this is not the case in the wild). Bean (1976) described the tree’s character in cultivation as ‘vigorous but rather graceless’. No cultivars have yet been selected, but there has obviously been a tendency to clone Wilson and Forrest’s original collections such as W 4088 and W 983. Perhaps most of the original seedlings disappeared or died, and increasing reliance was thereafter placed on vegetative propagation from those few that were kept and allowed to become specimens.

Two Sichuan-provenance seedlings of Betula pendula subsp. szechuanica dating from 1979 (Stone Lane Gardens, Devon, UK; 3 December 2022). Image Julian Sutton.

Bark of Betula pendula subsp. szechuanica (Stone Lane Gardens, Devon, UK; 3 December 2022). Image Julian Sutton.

The UK champion Betula pendula subsp. szechuanica at Bodnant in north Wales in May 2016. In this subspecies, even the scar tissue that heals the wounds left by shed branches is pure white. Image Owen Johnson.