The future of British broadleaves held in trust

The future of
British broadleaves
held in trust
The Future Trees Trust (FTT) chose well for ‘Supporters’ Day’
on May 14, virtually the first day in the month without
rain, and within the sylvan splendour of Westonbirt
National Arboretum in Gloucestershire. Organised by Tim
Rowland (Development Officer, FTT) the event was well
attended by a good cross section of the tree world,
including foresters, nursery owners, researchers, academics
and representatives of major charitable organisations.
Supporters were briefed on the FTT’s aims and achievements and two tripartite projects in which the FTT is a major stakeholder – ‘A Future with
Broadleaved Trees’ (FTT, Earth Trust and Forest Research) and the ‘Living
Ash Project’ (FTT, Earth Trust and Sylvan Trust). A rustic lunch was followed
by an authoritative tour of the National Arboretum by the Forestry
Commission’s John Weir, who gave a snapshot of the tree diversity at the
fingertips of foresters, building on a major theme of the day.
The Living Ash Project, and, to an extent, A Future with Broadleaved
Trees, are reminders (if anyone needs them) of how one exotic tree disease
called Chalara ash dieback, and now the resident ‘elephant in the room’,
has changed the game far beyond the narrow confines of a single native
broadleaf tree (Fraxinus excelsior – common ash), and even beyond the
frontiers of forestry. As is often the case at such events, those things not
mentioned or elaborated on are invariably as important as those that are.
John Weir (right) of the
FC: “This Quercus robur
would have originally
been grown for timber,
but is now more valuable
as a genetic resource.”
Setting the scene
Graham Taylor, co-chairman of the FTT, set the scene. The FTT was established 23 years ago as a core group, and has since been building bridges
and forging links nationally and internationally. “Seven species groups have
been established, with more on the way,” he said.
If this is the last chance saloon for breeding improved broadleaves, then
you only have to look at early systematic deforestation of Britain, and how
the chickens have long since come home to roost.
Modern history shows Britain’s forest cover has been comparatively low
for at least three millennia – 20 per cent at the time of the Roman invasion,
15 per cent by the time of the Norman conquest and just 5 per cent by
the end of the Victorian era, claimed Graham Taylor. It now stands at a
miserly 12 per cent, dangerously low and poor by European standards.
Actual biomass losses over this time have been more than matched by dysgenic selection, where the best timber quality trees go first. “That’s a really
nice timber tree – I wonder how much I would get for that?” commented
Graham Taylor.
“Until the FTT’s formation, virtually nothing had been done – but compare that with continental Europe,” said Graham Taylor, “with 300 to 400
years of selection and refinement in broadleaves.”
The proof of the pudding is in the eating. The Germans currently produce 54 times more sawlogs per hectare, and the French 45 times more.
“The UK doesn’t produce much broadleaf timber, and what there is has
poor quality,” said Graham Taylor. He compares this unfavourably with the
UK’s sustained breeding focus on Sitka spruce, increasing yield, form, vigour, marketability and sawmill conversion rates. “Without Sitka spruce
there would be no UK forestry,” admitted Graham Taylor.
Are broadleaves safe in government hands?
Next was Ian Gambles, Director, Forestry Commission England. “What
changes would I see in UK forests and forestry if I came back as a very old
man?” he asked. He was very confident that publicly owned forests would
remain just that, with sufficient funding for the fundamentals of forest
research firmly in place, but he was less sure the CAP (Common
Agricultural Policy) would be around in 50 years.
Personally, I am not so sure about the public forest estate. I recall
Confor’s England Conference 2012 (Forestry Journal, November 2012)
shortly before the Bishop pronounced from his pulpit. Government politicians didn’t sound too reassuring then. The well connected MP representing the Conservatives said the government would not come back ‘for
another go’ [at the public forest estate] in this parliament, while the Liberal
Democrat peer sounded sorry that Forest Enterprise would not be dismembered. I asked some at the FTT Supporters’ Day for their views. One wellplaced delegate was confident about the future of the public forest estate,
but very fearful for the future of Forest Research.
Ian Gambles foresaw less state involvement in forestry and a retreat in gov-
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ernment financial support after many years of big contributions. “UK forestry must not rely on government support. Long-term future is all about
the market,” said Ian Gambles. “I am talking about ‘natural capital’ as well
as ‘financial capital’ investment,” he said, adding that he saw greater
respect for the former. “We must think about what we can do to boost the
stock of natural capital (ecology, landscape, leisure?) when considering the
current position of broadleaves,” he said.
He talked about unmanaged woodlands, insect pests, diseases and grey
squirrel damage, and an important role for the firewood market in consuming the ‘rubbish’, as well as market incentives for woodland owners to
invest in their assets. He sees the FTT as being right at the beginning of a
chain linking current work to the attainment of the best trees for the
future, and said the Commission was pleased to support the FTT initiative.
One delegate said the public forest estate was a resource waiting to be
tapped into for landscape and tourism, which was something we had singularly failed to capitalise on. Graham Taylor said this held true for broadleaf- and conifer-based forest and landscape.
Ian Gambles saw an increasing role for a charitable organisation like the
FTT alongside the private sector to take over where the government would
presumably leave off. His message to UK forestry was that it must look
elsewhere (other than government) for future financial support. Tim
Rowland’s comments about the unique relationship now forged between
the FTT and Tubex proved particularly pertinent in this respect. Tubex has
given £30,000 to the FTT over the last two years and received valuable
marketing opportunities in return, claimed Tim Rowland, adding that the
FTT is looking to build this sort of partnership with a suite of other donors.
Tim Rowland made the very important point about how Chalara ash dieback had actually raised the FTT’s profile and focused attention on the
need to do something quick and clear cut about native broadleaves:
“Every cloud has a silver lining.”
This same point was made by Pauline Buchanan Black, Director General
of the Tree Council. “Cometh the hour, cometh the man. Cometh the disease, cometh the man,” said Pauline, referring to the foundations of her
own organisation back in 1973 in response to the ongoing slaughter of 25
million elm trees by Dutch elm disease. Chalara ash dieback has provoked
activity across the board and far beyond the frontiers of a single native
broadleaf tree. It has certainly given the UK government a ‘shot in the
arm’ (to put it politely). Perhaps we should look upon the event as an
opportunity rather than a disaster.
www.forestryjournal.co.uk
Forestry Journal 6/14
Living Ash Project
The next session was all about common ash and Chalara ash dieback – the
‘Living Ash Project’ – and was delivered by Dr Jo Clark of the Earth Trust in
Oxfordshire. Jo Clark described how 20 years of ash breeding and improvement on the very cusp of fruition was beaten by a hair’s breadth following
the spread of Chalara into the wider environment (October 2012) and the
ensuing planting ban. This effectively consigned all those years of work to
a sack (of seed), said Jo Clark. The current task is to match superior timber
qualities painstakingly selected and refined over two decades and with a
high tolerance to Chalara. “With Danish figures showing a 1 per cent frequency of tolerance to Chalara, we can expect 4 out of our 400 ‘plus’ trees
to show tolerance,” said Jo Clark.
The Living Ash Project has retreated from ‘resistance’, apparently realising that in plant pathology terms, no resistant ash trees have yet been
found. For that to happen, leaf infections would need to be isolated and
destroyed almost immediately by cells and tissue in the living ash leaf –
referred to by plant pathologists as a ‘hypersensitive response’. All ash trees
are susceptible to infection by the Chalara fraxinea fungal pathogen, but in
some trees the ensuing disease has a miniscule effect. Jo Clark said this
would typically amount to less than 10 per cent crown dieback, and essentially be unnoticeable to the untrained observer.
She described how they were working with the public using citizen science and ‘AshTags’. Members of the public are encouraged to purchase
these aluminium tags and the nails required to secure them to a tree.
Purchasers are sent an accompanying pack which explains how to plot the
disease (Chalara) on the tagged tree. They cost £4.99 for a pack of five,
plus £1.00 postage.
The main aim of AshTag is to, “Track down resistant trees that can be
used to fight back against this devastating disease.”. We were offered free
‘ash tags’, but I declined. Tolerance may be genetically controlled, but age
and environment will also play a part, with older trees generally showing
more tolerance to disease in general, so what’s the point in tagging and
monitoring a 50-year-old ash tree in the hope of identifying tolerance to
Chalara ash dieback, and subsequently using the germplasm in a tree
breeding and improvement programme? You can’t possibly know how the
tree would have reacted 45 years ago if Chalara was present in the UK, and
the tree, then a five-year-old sapling, became infected.
Surprisingly, no mention was made of the emerald ash borer, currently
all over the Moscow region of Russia and moving full steam ahead to the
nearest EU country (Latvia). Projections for arrival in the UK indicate
appearance just in time to consign another 20 years of ash improvement
work, this time to the coffin.
What’s in store for tree seeds?
Rob Lee from Forestart talked about the practical problems of seed collection, including site specifics such as slope, ground vegetation, drainage,
site access and security. Evidence of potentially predatory wildlife, including
deer, wild boar, grey squirrels and pheasants, is also important considerations. In high density stands, tree crowns are invariably too small to produce significant amounts of
seed.
The FTT seed stand audit
involves collection, making
more sites available and
identifying shortages where
they exist. There is a general
shortage of seed for all
broadleaves in Scotland and
Wales, including native
white oaks and especially
Quercus petraea, which does
not crop as frequently as Q.
robur. Scottish stands tend
to be located in hostile environments, with harsh and
demanding conditions that
make for very expensive
seed collection, said Rob
Lee. There is a lot of Q. petraea in Cumbria.
Pauline Buchanan Black, Director General of the
Tree Council, ‘getting to know’ an oriental spruce.
Forestry Journal 6/14
There are no collectable
stands of silver birch in
England. Mixing and hybridisation with downy birch cause seed purity
issues. Seed orchards are the way to go for birch, said Rob Lee. There is a
good geographic spread of beech stands, but deer predation is a big issue.
Sycamore also has purity issues because nets put down to catch sycamore
samaras collect other material, amongst which common ash and field
maple samaras are presumably prominent. Orchard seed material is the
way forward for sycamore, said Rob Lee.
“There are simply not enough sweet chestnut seed stands, which is now
becoming critical because we cannot import seed,” said Rob Lee. “Sweet
chestnut harbours a lot of ground vegetation, which makes seed collection
difficult,” he said. There is just one stand of small leaved lime.
The proportion of UK-selected material in the 2013 collection – pedunculate oak 50%, sessile oak 50%, silver birch 3%, beech 90%, sycamore 60%,
sweet chestnut 35% and small-leaved lime 0% looks quite good, said Rob
Lee, concluding his presentation on FTT’s Seed Stand Audit.
My cup runneth over
Jayne Manley, CEO of the Earth Trust, gave two presentations – ‘Update on
‘A Future with Broadleaved Trees’ and ‘Training the next generation of
tree-breeders’. Any hope for the former clearly depends on some quick
action with the latter. She likened the ‘battle for broadleaves’ to a military
operation and said coming up with a strategy had required tankards of
wine and caused many grey hairs.
“Different people value different things and we have to identify what
these are while not losing sight of the economics of woodlands,” said
Jayne Manley. Pauline Buchanan Black wanted to know exactly who are the
people this is aimed at, and how will they be reached: “I mean, is it the
person who goes to Homebase to buy garden furniture and who has absolutely no knowledge of these strategies, and via A future with Broadleaved
Trees, Grown in Britain, etc?”
Training the next generation of tree breeders (and plant pathologists) is
clearly the ‘silver bullet’ to any success. Our trees are getting older and our
sylvan scientists even older (relatively), it being increasingly difficult to buttonhole anyone much younger than fifty at such gatherings. Leaving specialist education in plant breeding and plant pathology to the university
marketplace has clearly not worked, and neither will it when there are bigger and quicker-cooking fish for university chancellors to fry. Perhaps the
answer is for the government to subsidise the appropriate university courses and promise to keep them open even if they lose money – and even
‘bribe’ students to enrol.
No one had yet mentioned genetic modification – an altogether quicker,
cleaner, more accurate and probably cheaper approach to tree improvement. What’s more, our universities and research organisations are brimming with molecular biologists and geneticists who don’t even need to go
into woodland to do the work.
On the stump
Last, but not least, we all enjoyed a highly informed tour of the Arboretum
by John Weir, advisor for woodland creation and resilience at Forestry
Commission England and part of the FC’s Diversity Team. First port of call
was an immaculate Quercus robur – fitting, since Bede Howell had previously presented Oak: fine timber in 100 years, his English translation of a definitive text originally published in French as Le cheune autrement. But no one
had yet mentioned Acute Oak Decline, clearly the single biggest barrier to
‘fine oak timber in 100 years’. Harking back to Graham Taylor’s point about
dysgenic selection, John Weir said, “This tree would have originally been
grown for its timber, but is now far more valuable as a genetic resource.”
Those suffering conifer withdrawal symptoms finally got their fix. We
saw and ‘hugged’ huge specimens of Cryptomeria (Japanese red cedar), oriental spruce, coast redwood, the deciduous dawn redwood and some
remarkably tall, timber-tempting English yew.
John Weir sparked a lively debate throughout, including a ‘spat’
between foresters and a nurseryman about the need to plant a wider range
of species. The nurseryman said it was all very well asking him to plant
‘funnies’, but he had to be sure there would be a market in five years’
time. Someone suggested the government stumped up some money so
that nurseries could plant ‘funnies’. A figure of £100,000 (in total), was
mentioned, but, given the current economics of forest nursery production,
that sounds like ‘very funny money’ to me.
Dr Terry Mabbett
www.forestryjournal.co.uk
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