TREE OF THE MONTH
Common beech
Common or European
beech (Fagus sylvatica)
is the only naturalised
deciduous premium
hardwood tree now free
from potentially life-
threatening exotic insect
pests or pathogens. Is this
what’s left for UK forestry
in the way of mainstream
native hardwood timber
trees? Dr Terry Mabbett
has been carrying out his
own research.
A
S one of the last tree arrivals after
the last ice age, beech was unable to
naturally colonise the entire British
Isles. A line from The Wash to south-
east Wales is generally accepted as
the limit of its natural spread.
Things have turned around for the beech
tree. Just 16 years ago proponents of climate
change had marked its card as the first
casualty of a warming UK climate. Seeds of
doubt sown late last century after a series
of hot dry summers came to the fore in 2001,
with the Woodland Trust’s publication of
A Midsummer Night’s Nightmare – The
Future of UK Woodland in the Face of
Climate Change. This had beech as a noble
protagonist, normally sweeping all before
it, but now flawed, set to suffer a quick and
fatal end. Using science-light arguments, it
predicted the departure of British native trees,
with beech first to disappear in southern
England by around 2050 – 32 years from now.
Seriously doubting the validity of such
wild-sounding claims, I embarked on my own
research in South Hertfordshire, where beech
grows alongside at least a dozen other native,
naturalised and exotic tree species in semi-
natural ancient woodland. The essential points
for continuation of beech as a procreative,
permanent native in Britain’s semi-natural
woodland are:
Are mature beech trees setting viable seed?
Are beech seeds germinating in these
woodlands and are seedlings successfully
establishing?
Are young beech trees putting on sufficient
extension growth to compete with other
high forest native trees (e.g. oak, ash and
hornbeam) and naturalised equivalents like
sweet chestnut and sycamore?
Are beech trees suffering a shortened
life expectancy from physical and/or
physiological damage (including disease)
relative to other native climax forest trees?
BEECH REVISITED
These hypotheses were tested in four semi-
natural, mixed broadleaf woodlands: Hadley
Wood, Leggatt’s Wood, Little Heath Wood and
Northaw Great Wood, during early autumn
2011 after the extension growth period for
beech had ended. Extension growth was
measured for twenty randomly chosen shoots
up to 3 m high on ten young trees.
CBH was measured in cm for each tree, with
tree height estimated in metres. In addition,
species, CBH and growth pattern of every
tree within a 10 m radius of each beech tree
were recorded to give an idea of the woodland
profile and a measure by which inter- and
intra-species competition could be assessed.
Selected mast-bearing trees in Hadley
Wood, Little Heath Wood and Northaw GreatWood were assessed for seed load according
to size, age and maturity of trees. One large,
mature beech of at least 300 cm CBH was
selected from each of Little Heath Wood,
Hadley Wood and Northaw Great Wood, and
one much younger mast-bearing tree from
Little Heath Wood and Northaw Great Wood.
Beech nuts along an accumulated shoot length
of 4.5 m were counted and the mast load
expressed as number per unit length of shoot.
All beech trees inside a 100 m x 30 m area
on the western extremity of Hadley Wood
with a CBH of at least 200 cm were identified
and measured to the nearest 1 cm. They were
ranked in order of size, with windblown or
dead standing trees, including stumps, or
living but visibly diseased trees, noted. In all,
21 trees were identified and assessed.- from seemingly lost cause
to increasingly rare hope
FORESTRYJOURNAL.CO.UK MAY 20 18 69A veteran beech
tree: onward and
upward, in one of
Hertfordshire’s
semi-natural ancient
woodlands.