It was predicted to be an early casualty of climate warming in the UK, but is the outlook for beech brighter than many assumed?

COMMON beech (Fagus sylvatica), which old-time foresters and woodsmen fondly called the ‘Mother of Forests’, is a British native tree, but only just. Along with hornbeam, with which young beech trees can easily be confused, beech was one of the last tree species to cross the land bridge with Europe after the last ice age. 

According to some accounts which surfaced towards the end of the 20th century, beech would be one of the first native-tree casualties of climate warming, predicted to disappear from southern England in a matter of decades. Twenty years on, climate change is indisputably real, though predictions on temperature rises made then were clearly over-cooked.

However, before considering any potential exit of beech trees from parts of the British Isles, it is worth considering how the species managed to establish and compete with already well-established tree species many thousands of years ago. This may well provide clues to any continued success of beech into the foreseeable future.


When beech arrived on the land mass now comprising Great Britain, it would have been faced with well-formed forests and few available niches in which to establish – perhaps the reason for its apparently slow spread west and north. Indeed, the natural spread of common beech is considered to have stopped at a line drawn from south-east Wales to the Wash, with any beech found beyond this limit carried there and planted by man. Beech may have been slow, but colonise it did, with the species becoming an important native climax tree of semi-natural woodland across southern England. 

A trio of well-known and understood features of Fagus sylvatica almost certainly assisted with colonisation:

• Beech possesses a comparatively shallow root system which exploits surface layers of the soil profile, mopping up water and nutrients at the expense of competing plants including other tree species.
• Beech displays a foliar geometry which effectively excludes light from reaching the forest floor to give tree an additional competitive advantage.
• With assistance from mammals and birds which predate on its nuts (seed), beech can establish groups of seedling trees around the parent tree, which grow to form a grove of mature beech trees and the stepping stone to eventual formation of pure beech woodland.

Early botanists and foresters recognised how beech always competed strongly with other woodland trees, including English oak, traditionally called the ‘Father of the Forest’. ‘Father of Forestry’ John Evelyn, writing in his 17th-century Sylva, said: “Where mixed woods of oak and beech are left to their own devices, they ultimately become pure beech woods.” He ascribed this to extensive rooting in the surface layers of soil and depletion of the food elements therein, leaving none to penetrate into deeper layers where the English oak tree has its roots.

Forestry Journal: Late summer into early autumn with beech mast now fully developed. The bristly cupule (fruit) will soon split and release the angular, three-sided beech nuts.Late summer into early autumn with beech mast now fully developed. The bristly cupule (fruit) will soon split and release the angular, three-sided beech nuts.

Fast-forward four centuries to the late 1900s, when a succession of hotter and drier summers began to spook climate scientists, who claimed the same shallow root system which had allowed beech to compete successfully with other native trees would prove to be its Achilles’ heel. Well-established perceptions that the natural home for beech is well-drained chalk and limestone soils augmented this belief.

By the year 2000, the Forestry Commission had released research which appeared to confirm beech had been adversely affected by a succession of dry summers during the final two decades of the twentieth century. Observations made since 1984 using visual assessment of crown density (degree of transparency or leafiness of the crown) revealed a worrying trend. Foliar crown density reductions in beech exceeding 25 per cent, and subsequently used as a specific indicator of climate change, were recorded in 1987, 1989–92, 1995 and 1997 following dry summers.

Around the same time, reports commissioned by the National Trust, the Royal Horticultural Society (RHS) and the UK Climate Impacts Programme (UKCIP) predicted significant temperature changes over the next half-century, with summer and winter temperatures rising by 2–5 °C and 2–3 °C, respectively. 

A rise in temperature of 1 °C is equivalent to a 100-mile shift south. Any tree species planted outside of its normal climate range will suffer physiological stress, with loss of vigour and lower tolerance of pests and diseases, and beech trees in southern England would be under increasing stress without having moved an inch. 


The Mother of the Forest reaches the heady heights of 30–40 m, with a bole diameter up to 3 m at maturity, all within some 120 years. Beech trees clearly grow faster than English oak in the same woodland situation, but do not last anywhere near as long.

Maiden beech trees can live for up to 300 years, although 200 years is a good innings for a beech tree, with anything much in excess of two centuries beyond the beech tree’s sell-by date, unless the tree is a beech pollard. Epping Forest is one of the best places to see classic old beech pollards. These 500-year-old trees are actually lapsed pollards which have not been lopped for 100–200 years, but their history of pollarding, though ceasing at least a century ago, has contributed to their longevity.

When planted in open spaces, the beech tree forms spreading branches near its base, with the broad crown providing good shelter. When growing adjacent to other trees inside woodland, the beech tree shoots up to the light, branching more towards the summit, leaving behind a tall, naked and columnar bole with a leaden-grey and smooth bark, which covers a pale-brown hardwood that is relatively easy to work. Traditionally, in Britain, the whiter the wood, the higher its value for timber. 

Forestry Journal: Close grouping of beech seedlings can eventually lead to a pair of large mature beech trees growing side by side.Close grouping of beech seedlings can eventually lead to a pair of large mature beech trees growing side by side.

Winter twigs with their long, sharp buds are among the sleekest of the deciduous woodland. In spring, just before the buds start to expand, beech twigs are distinguished by long, slender buds borne alternately along the twig, the brown scales retaining their intrinsic shape long after they are shed at bud burst.

Beech trees start to re-leaf in mid-April. New leaves are folded ‘fan-wise’ in the bud with the folds running parallel to the veins and expanding into the most verdant green foliage. The oval-shaped leaves are smooth-faced with slightly scooped edges. A delicate fringe of gossamer present around the margin of the leaf as it comes out of the bud will fall off as the leaf hardens and darkens, with accompanying development of a glossy sheen. The now dark-green, shiny and leathery leaves persist right through summer into autumn, when they assume a rich, ruddy brown colouration before coming down in a cloud in late-autumn wind and rain.

At around 20 years of age, the beech tree will start to produce flowers. The separate male and female flowers appear in May when the tree is in full leaf. Several groups of female flowers are clustered within a ‘cupule’ of overlapping scales, positioned near the shoot tip, while the male catkins hang together in a purplish-coloured tassel further back along the branch. The format of beech flowers and flowering is similar to that of the botanically related English oak, though much more conspicuous. 

Be that as it may, the flowers of both beech and oak are likely to be overlooked by the casual observer, although definitely not the fruits and seeds (beech nuts and acorns) of trees in the plant family Fagaceae. In beech, the cupule becomes a bristly closed ‘box’, the beech fruit, which on maturity opens by one of its ends splitting into a quartet of triangular, silk-hair-lined valves. They peel back to reveal the three-sided, sharp-edged beech ‘mast’ or beech nuts.

By October, the cupped woody fruits, now covered in soft spines, have ripened and continue to fall through winter, spilling their contents under the tree. The three-sided nuts, two to three per fruit, are the source of much speculation about the reproductive habits of the beech tree. They occur in abundance, but only once every five to eight years during a so-called ‘mast’ year. 

The erratic production of seed, which is common in temperate trees and most pronounced in beech, appears to confer some long-term advantage to the species. The main predators of beech mast are seed-hoarding birds and mammals, with the most successful of these predators able to stash away sufficient supplies to meet their needs in case of harsh winters. 

These relatively long-life-cycled animals are unable to adapt to the irregular reproduction rate of the beech tree, so every year will continue to store the same amount of seed which in mast years represent only a small proportion of the total seed load of the tree.

Net result, and especially in mast years, is more seed left in the ground to germinate with consequent bunching of trees of the same age that is so characteristic of beech woods. This confers an evolutionary bonus and allows trees to gain from growing in a group creating their own microenvironment.

In the early spring, among dead leaves cast the previous autumn, the triangular beech nuts will germinate to generate tiny seedlings, each with a pair of seed (cotyledon) leaves resembling a pair of butterfly wings. Only with further growth and the appearance of the first pair of true leaves will the uninitiated realise they are looking at the first signs of life in the next generation of beech trees.


One of the most drastic predictions about the consequences of climate warming came from a report commissioned by the Woodland Trust in 2001, suggesting beech could disappear from the south of England by 2050, if not sooner. So taken aback was I by these dire predictions that I carried out extensive research over several seasons, starting in 2008. The study took place inside a range of woodlands (some ancient) in south Hertfordshire and North London. 

Forestry Journal: This author monitoring beech mast in Northaw Great Wood in Hertfordshire circa 2010.This author monitoring beech mast in Northaw Great Wood in Hertfordshire circa 2010.

I monitored radial growth (bole diameter and girth at breast height – dbh and cbh), tree height, extension (shoot) growth, tree regeneration from seed, fruiting, longevity, damage caused by abiotic (e.g. wind damage) and biotic (e.g. fungal infection) factors and mortality. This provided an assessment of whether beech tree populations in this corner of southern England were showing significant signs of stress, per se and/or in comparison to the other climax forest tree species. 

A complete range of beech trees by size and age were used, including seedlings, saplings and immature (pre-fruiting) trees, to assess parameters like regeneration from seed and extension growth, mature trees (including veteran and ancient specimens) for structural damage, mortality and longevity. And a complete age/size range of trees for radial growth – bole diameter and circumference.

The results are far too extensive to present here, but suffice to say beech in my neck of the woods was not suffering any visible stress – certainly no more than other tree species like hornbeam.

Within the realms of native and naturalised climax-forest trees, beech is a fast-growing species, but appears to be more susceptible to damage and early failure with advancing age. The longevity of maiden beech is significantly less than comparable species like English oak, sweet chestnut and English elm. 

In open spaces like village commons, estates and large gardens, beech produces huge spreading branches near the base, leaving trees susceptible to major branch failure. This may disrupt the balance and stability of old trees, making them highly susceptible to terminal wind damage. In this context, William Wordsworth made specific reference to the Alfoxden Beech in Somerset, which he described in 1798 as the most amazing beech, with huge spreading lower limbs (one already snapped off by wind) he had ever seen. On returning in 1841, he could find no trace of the tree, which had been blown down years before.  

Woodland beech, in contrast, shoots straight up to the light, branching more towards the summit, leaving behind a tall columnar bole. The vitality of beech is such that the bole frequently divides at its upper part into several trunks, which rise straight up, each attaining the dimensions of a complete tree. This creates different but equally significant problems related to high load bearing and susceptibility to wind damage, with cleavage at the point of division not an uncommon occurrence.

Forestry Journal: Mature beech leaves in late summer, hard and glossy with next season’s sleek winter buds already in evidence.Mature beech leaves in late summer, hard and glossy with next season’s sleek winter buds already in evidence.

There is no strong evidence to suggest climate warming will cause beech to disappear from southern England within the time scale suggested some two decades ago. However, there are other factors affecting its longevity, including pollution, pests and diseases.  

The most perverse non-climate-warming threat to beech was purely man made. Some 20 years ago, when predictions around climate change and its impact on trees and woodland started to heat up, large areas of beech were still being removed from woodlands in the north and west of the British Isles, including Cumbria, North Wales and even the East Midlands. This was on the grounds that common beech was not native to these areas – anywhere north and/or west of a line from south-east Wales to the Wash, which is on the east coast of England between Lincolnshire and Norfolk. 

At the time, I thought it was foolhardy. When asked why this was being done, the answer given was ‘to protect true native tree species like common ash (Fraxinus excelsior)’.

Following the arrival of Chalara ash dieback in 2012 and the fungal pathogen’s subsequent decimation of common ash, I guess it was the turn of the perpetrators to feel foolish.