Betula woods rarely form on chalk although B. pendula is frequent on pure limestones. 

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Rackham (1980) detected no significant present-day ecological differences between B. pendula and B. pubescens in England. It is distinguished from the related Downy Birch (B. pubescens, the other common European birch) in having hairless, warty shoots (hairy, without warts in Downy Birch), and whiter bark often with scattered black fissures (greyer, less fissured, in Downy Birch). It is also distinguished cytologically, Silver Birch being diploid (with two sets of chromosomes), whereas Downy Birch is tetraploid (four sets of chromosomes). Betula pendula is one of the most common native British trees but is also widely planted and is abundant throughout the British Isles, although not reaching the far north of Scotland or Ireland, where B. pubescens is favoured. Although closely related, it does not usually hybridize with B. pubescens. although some research believes that there may be some form of hybridization.

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A pioneer species, it readily invades old fields, cleared or burnt-over land and creates conditions suitable for other woodland trees to become established. It forms an upper cliff zone above ashwoods of the Carboniferous Limestone in the northern Pennine region. It also forms a distinct pre-climax phase in the succession to oakwood on light sandy siliceous heath soils (Tansley, 1939, Rodwell 1991). British Betula are typically pioneers in two types of habitat (Atkinson 1992): forest or heathland recently cleared by felling or fire either in gaps left by canopy trees or as primary colonisers, and in habitats climatically or edaphically unsuitable for other trees, in upland zones or on peat bogs. Thus birch forest forms an altitudinal zone above and a latitudinal zone to the north of oak forest in the British Isles (Tansley, 1939). Betula species often form pioneers in the passage from heathland to forest. They are frequently associated with Quercus in oakwood on a great variety of soils (Gimingham 1984, Rodwell 1991), though not when the oaks form a close canopy, as Betula cannot tolerate deep shade and will not regenerate successfully (Kinnaird 1974). Betula pendula is also an important component of Quercus-Fraxinus excelsior woods (Gimingham 1984). The several woodland communities in which Betula is important are described by Rodwell (1991).

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Betula tends to improve acidic poor soils, increasing pH and nutrient status (Atkinson 1992). Since it is relatively short-lived and intolerant of shade, it is eventually out-competed by these trees. Thickets will appear on any vacant soils as long as there are no animals grazing. Betula pendula prefers drier, lighter soils (Gimingham 1984, Atkinson 1992) and some birchwoods are almost permanent in the south east Highlands and on the few remaining sandy heaths and commons in England, particularly Sussex (Wilkinson, 1976).  

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Birch is found throughout most of the UK and Europe and across Asia. The closely related Siberian Silver Birch (B. platyphylla) in northern Asia and Sichuan Birch (B. szechuanica) of central Asia are also treated as varieties of Silver Birch by some botanists, as B. pendula var. platyphylla and B. pendula var. szechuanica respectively. One of the reasons why birch managed to colonise the newly emerging lands following the retreat of the glaciers lies in its abundantly-produced seed, as fine as powder. Even today, it remains what botanists call a ‘pioneer’ species, one of the first trees to occupy suitable ground. That said, it is not a long-lived tree; most specimens die or succumb to fungal attack by the age of 70. However, they do offer protection to slower-growing, longer-lived tree species such as oaks, and where left to regenerate birches can play an important role in helping to nurture a wood. 

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As Betula is wind-pollinated and produces abundant, well-dispersed pollen it is very well represented in Holocene and earlier pollen records, even over-represented to the degree where correction factors need to be applied to its counts to relate them to actual tree Betula populations (Andersen 1970, Bradshaw 1981, Dickson 1984). Betula pollen has been recognised from all stages of the Quaternary (West 1980), with macrofossils of Betula pendula recovered from the Late Anglian (Oxygen Isotope Stage 8 or 10) cold stage (Godwin 1975) as well as pre-Holocene interglacials. Betula pollen and macrofossils are also well represented in sites throughout the Devensian glacial period, although often as B. nana. At Chelford, Cheshire (Simpson & West 1958), however, temporary warmer conditions about 60,000BP allowed the development of boreal woodland with tree Betula. Tree Betula pollen is a key environmental indicator of warming conditions at the end of glacial stages. During the Devensian late glacial between c.15,000 and c.10,000BP frequencies of tree Betula pollen are taken as a proxy record of climate change, their increase after c. 13,000BP signifying higher, interstadial temperatures followed by their sharp fall during the Younger Dryas (Loch Lomond Stadial) cold phase between 11,000BP and 10,000BP (Birks 1986). The sharpest reductions in Betula pollen were in Ireland at this time due to very cold sea temperatures (Watts 1980), and less marked further east. The complex climatic fluctuations of the Late Glacial produced a correspondingly complex, multi-peak Betula pollen curve at some sites in northern Britain (e.g. Bartley et al. 1976). Betula pollen is most abundant, however, in the pre-temperate and post-temperate phases of the interglacial climatic cycle. Its hardiness and rapid dispersal allows its early arrival and rapid spread before the other deciduous temperate trees arrive (Atkinson 1992). Its very rapid population expansion rates in the early Holocene have been demonstrated by Bennett (1983, 1986) and isopollen maps have been presented by Birks (1989) showing the spread of Betula woodland across almost all of the British Isles from the east from slightly before 10,000BP. Betula woodland was dominant in many parts of Britain and western Europe between 10,000BP and 9,000BP (Huntley & Birks 1983) after which it declined due to Pinus and Corylus immigration (Birks 1989). Betula bark scrolls at the Mesolithic archaeological site of Star Carr c. 9,500BP (Clark 1954) indicates that humans found uses for birch products from the earliest Holocene and the use of Betula timber for trackways and other artifacts continued throughout prehistory. As in preceding interglacials the rise of the mesocratic mixed oak forest (Birks 1986) severely reduced the available habitats for Betula although it survived in the north of Britain, as in the Western Isles, and around the tree line at high altitude. Elsewhere Betula pollen values are very low during this time and Betula had to rely on the creation of gaps within the dense deciduous forest or on very marginal environments such as drying bog surfaces. These latter were quickly colonised, and subsequent wetter conditions and peat regrowth can be recognised by a layer of birch stools just below the recurrence surface. Similar layers often occur on mineral soils beneath high altitude blanket bog, as in the north Pennines  which marks the onset of paludification. Even when the Betula wood itself has not survived, resistant layers of white bark remain easily recognisable. In these wetter locations the remains are often of B. pubescens. Prior to the introduction of farming and its associated forest clearance the creation of breaks in the forest canopy would probably have been confined to the results of storms and wildfire, both of which would have removed established trees and allowed successions to begin in which Betula could flourish briefly. The use of fire in the forest by Mesolithic people may well have contributed to this (Simmons 1996) and Betula pollen frequencies rise sharply during post-fire regeneration at this time. From the start of the Neolithic period onwards human disturbance of the deciduous forest created ever more open habitats for colonisation by Betula and higher Betula values are a consistent feature of the pollen record during and after Neolithic and later forest clearance. The almost complete removal of British woodland by prehistoric and later farmers has replaced the natural changes which would have taken place in the tree flora during the last 5,000 years. Reference to earlier interglacials shows, however, that in the telocratic, later stages of an interglacial Betula is favoured again as climate and soils deteriorate and more thermophilous trees decline (West 1980, Birks 1986). The increase in Betula pollen percentages caused by human activity since c.5,000BP would very probably have occurred in the later stages of the Holocene due to natural climatic and edaphic change.

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Pollen grains of Betula pendula are triangular or oval in side view, and have a well ringed and shouldered pore (Andrew, 1984). They are distinguishable from the very similar grains of B. pubescens by the latter's more hooked and sharply shouldered pores. Prentice (1981) has separated Betula pollen grains using size frequency data. Tree birch pollen grains are more easily distinguishable from dwarf birch (B. nana) grains (Birks 1968).

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