The ash grove, how graceful, how plainly ‘tis speaking/ The harp through it playing has
language for me. Growing up in New Zealand, I knew fragments of this song and
would sing them on car trips with my family long before I actually ever met an
ash tree in real life. When I did so at last, I was underwhelmed. Ashes in full
leaf are certainly graceful, but they’ve never really caught my imagination.
Not surprisingly, European ash groves evoke no wistful memories of childhood.
The leafless ash, though, is a different story: it’s been my
key to a new way of seeing the woods in winter. For years, they were just an
indistinguishable mass of bare trunks and branches. Then one day I happened
upon a reference in a book to the “jet-black buds” of ash trees. Black buds? I
began to look more closely. And lo and behold, walking through my local reserve
one day, I found a tree that did indeed have bold, black buds. And then
another! A whole grove of them! It wasn’t just the colour that was distinctive,
it was the shape, the energetic upward curve of the twigs, the symmetrical
cluster of the three buds at the tip, vaguely reminiscent of the club in a pack
of cards. Suddenly I was seeing them everywhere, and many of the gnarled old
trees I’d taken to be oaks turned out to have been ashes all along.
Since that discovery I’ve seen the winter woodland with different eyes. It’s no longer an undifferentiated and uninspiring background, but a varied cast of characters. I can’t identify them all, but it’s an enjoyable challenge. The clues are not just in the buds, but in the bark, the trunk, the arrangement of branches and twigs, the tell-tale leftovers of previous seasons: catkins and cones, clusters of winged seeds or “keys”. Some ashes – presumably those that bear female flowers, or flowers of both sexes(the sex life of ashes is complicated, to say the least) – are draped with untidy looking keys throughout the winter. It’s not their most attractive feature. Come spring, they put on a curious display of flowers: sprays of green stalks with purplish tips. Not the kind of obvious beauty that will win prizes in flower shows, but rather fascinating.
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Ash buds. Crabchick on flickr, https://creativecommons.org/licenses/by/2.0/legalcode
| Ash flower. Dean Morley on flickr, https://creativecommons.org/licenses/by-nd/2.0/legalcode
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Old ash in Admiral's Park, Chelmsford |
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The same tree close-up |
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Hollow ash on bank of the Wid |
Another tree that I’ve discovered fairly late in life is the
elm. I didn’t expect to find elm trees when I came to Europe; I assumed they’d
all been wiped out by Dutch elm disease. News of that disaster had made it all
the way to my science classroom in New Zealand in the 1980s. But then while
visiting friends in Wales a few years ago I spotted a majestic tree with round,
winged seeds and curious asymmetrical leaves, one side extending further down
the stem than the other. I took a leaf home to compare with my tree guide, and
was delighted to learn that this was an elm. Since then I’ve found more elms in
hedgerows and parks around Chelmsford, though none anywhere near the size of
that tree in Llanberis.
These smaller trees are inconspicuous in summer, melting
into the background greenery. They’re at their most striking in spring, when
abundant clusters of winged seeds appear on bare branches. From a distance an
elm in fruit looks as though it’s covered in pale green blossom. It’s a lovely
sight, and this spring I’ve seen more and more of it on roadsides near
Chelmsford. My latest elm-related discovery, though, is the preceding phase:
the flowers. They’re easy to overlook, but unmistakeable once you’ve found them.
It was only this spring, in early March, that I noticed a few twigs with small
red flowers in my local reserve. What could this be, and why had I never seen it
before? A flick through my Collins Gem tree guide quickly brought enlightenment:
it was an elm! In
the weeks that followed I was able to observe the flowers morphing into fruits,
a remarkable transformation.
My elation at discovering elms was short-lived. On Easter
Day I was cycling around the countryside excitedly pointing them out to my
companions (could this have been a little annoying, I wonder?). Soon after
that, I noticed that one of the elms in my local nature reserve was surrounded by
dead trees of a similar height and build. Slender young trees, which had clearly
not died of old age. As the spring progressed, the difference between the
living and the dead became more and more obvious. I gradually realized that for
every healthy-looking fruit-laden elm I spotted in a hedgerow, there seemed to
be one or more gaunt skeletons nearby.
I take this as sobering evidence that Dutch elm disease is
still active and the species hasn’t made a miraculous comeback. So what is this
disease, and why is it “Dutch”? It turns out that it didn’t originate in the
Netherlands, nor does it particularly affect the species known as the Dutch elm. Somewhat unusually, it got its name from the
nationality of the scientists who first identified it in the 1910s. It is
caused by two related fungi, spread by elm bark beetles. The first epidemic,
from around 1910 to the 1940s, killed up to forty per cent of the elms in some European
countries. The second was much more severe, killing an estimated two thirds of mature
elms in the UK (some 20 million trees) in the decade following its accidental
introduction in the late 1960s. Most of the rest had succumbed by the early
1980s. It must have been a heartbreaking time for European tree lovers, and I’m glad I
wasn’t around to witness it. Today new elms keep growing up, mostly in
hedgerows, many suckering from the roots of dead giants. But the disease is
still lurking, and it seems that once these young trees reach a certain height
the bark beetles can see them and come in to feed, bringing the fungus with
them. All that hopeful growing for nothing.
Dutch elm disease is an old and well-known enemy, but
there’s a much more recent addition to the ranks of villainous tree-killing
fungi, and this one is going after the ash tree. Not surprisingly, given the
fate of the elm, there’s a considerable amount of anxiety about the resulting
disease, ash dieback or Chalara. The Woodland Trust gloomily predicts that it
will kill around 80% of ash trees across the UK; other estimates are even
higher. The disease was first identified in 2006, by which time it was already
widespread in continental Europe. The UK, however, continued to import ash
saplings from affected countries until 2012, when the first cases were found
here. This led to a sudden panicked response, with a ban on imports, the
destruction of 100,000 nursery trees and saplings, and a meeting of the UK’s
emergency committee. Too little too late, some have said – does this sound at
all familiar?
I only heard about ash dieback a couple of years ago and
I’ve so far been fairly unconcerned, since most of the ash trees I see around
me look pretty healthy. Just this spring, however, I’ve started to wonder. One
striking fact about ash is that it’s one of the last trees to come into leaf in
spring, and this being an extraordinarily late spring, they’re not quite there
yet. Most trees are now in partial leaf, but some are still almost bare. And looking at those bare trees, I’m having
my doubts. In the young, planted ash grove in my local nature reserve, there
are a few trees that are unquestionably dead, bark already peeling off, no
signs of life. Others look as though they might still be dormant – yet those
black buds have a slightly dry and shrivelled look. And elsewhere in the
reserve I’ve noticed that some of the mature ashes have a surprising number of
dead branches. Walking through the reserve recently, I started to look at the emerging
leaves with a sense of anxiety – is it just a late spring, or are these trees
actually unwell? It reminded me somewhat of waiting for a teenager to come home at night: as the evening
wears on you become increasingly anxious and begin to fear the worst – and then
at some point the child appears, slightly tipsy but otherwise unharmed, and
life goes on. Here’s hoping those ash trees that are starting to worry me will
soon be covered in healthy foliage, and I can put away my fears until next
spring.
It seems there’s little we can do about these diseases. Human
intervention – importing elm logs from North America and ash saplings from
continental Europe – has introduced these pests, but human intervention seems
more or less powerless to help their victims. In the case of Dutch elm disease,
felling affected trees has been the main strategy. Trimming the elms in
hedgerows to keep them out of the sight of elm bark beetles also seems somewhat
effective, but of course this means they will never develop their full
potential as tall and stately trees. As for ash dieback, the Woodland Trust
recommends that we clean our shoes or bike tyres after visiting the woods to
avoid spreading spores. This will sound painfully familiar to anyone who’s
lived in the northern part of New Zealand in recent years, where the efforts to
stop kauri dieback have hugely restricted access to the forest. As a keen
walker with an aversion to boot cleaning, I find this sensible advice rather
hard to swallow, but I suppose it’s a small price to pay if it does help combat
the disease. Now where is that scrubbing brush?
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Elm flowers, Chelmer Valley LNR, early March 2021 |
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Elm in fruit, Chelmer Valley LNR, mid April 2021 |
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Elm fruit, early May 2021 |
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Elm fruit and leaves, late May 2021 |
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Rare mature elm found in Chelmer Valley LNR, late May 2021
| Leaves of above tree
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Fallen twig from above tree with fruit |
Which
species of elms am I seeing, and are they all the same? The Collins Gem has two
main options, English and wych elm (
Ulmus procera and
Ulmus glabra
respectively); the flowers look similar but the fruits and the leaves are
slightly different, and appear in a different sequence: leaves first for
English elm, fruit first for wych elm. I can’t find mention of this elsewhere.
If the Gem is right then most of the elms I’m seeing are probably wych elms.
There are other options, though. Many of the small elms I’ve seen have
strangely ridged bark, even on quite slender twigs. It seems this “winged” or
“corky” bark is particularly typical of the Dutch elm (
Ulmus x hollandica)
and the small-leaved elm, also known as the field elm (
Ulmus minor). If
any readers know more, please get in touch!
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