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New Eyes For Old Yews


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'Seeing is believing' you may agree, but how about the other way round: do we learn a thing about nature and then see what fits our facts? Take churchyards for instance. You and I have heard that yew trees were planted there because the wall stops cattle and horses getting in, eating the leaves and being poisoned. Maybe your history teacher added that longbows were made from yew wood, so the trees had special protection until they were needed to shoot at French people. Obviously the church arrived first, then the chuchyard and the yews came next.

But maybe they didn't. The oldest tree in Oxford is a common yew (Taxus baccata) at St. Mary's Church in Iffley. That tree could be 1600 years old, whereas the church was built in 1170 - about half the age of the tree. That age has to be an estimate because the well-known method of counting the growth rings doesn't work with yew. Sometimes the width of the trunk does not increase for hundreds of years, because the trunk is hollow and an aerial root grows down the middle to rejuvenate the tree. In effect there is a tree within a tree. Sometimes the branches touch the ground, root and form a cluster of trees. The trunk of the Iffley yew is a hollow shell about 6 feet tall with thick, healthy branches at many angles.


Hollow yew tree trunk

Christianity arrived in Britain about 2000 years ago and took perhaps 1000 years to push aside earlier beliefs. The oldest church in Oxford for example was built in 1122 - it was St. Martin's at Carfax, demolished in 1820 but the west tower survives, dodging the buses and telling the time. There may have been wooden churches before stone-built ones of course, but all trace has been lost. The oldest tree in Britain (and in Europe) is at Fordingall in Perthshire, Scotland. Guesses at how old it is range from 2000 to 6000 years, with 3000 being the favourite. Putting these numbers together, you can see that an ancient yew may pre-date the church it stands by. I say 'ancient' here because the Victorians planted a lot of Irish yew (Taxus baccata 'Fastigiata'). You'll see many of their tall, green columns in cemeteries.

So where did the common or English yew come from? Some people say it was the original forest tree and that old trees survive only in churchyards because they've been wiped out everywhere else - maybe for making longbows. Others say the yew were planted in sacred groves by pre-Christian religions at places important to the believers - burial mounds, hill forts, beacon fire-sites and so on. Fordingall for example has a Bronze Age tumulus and it's said to be near the geographical centre of Scotland - but don't ask me how to work that out before satellites came along, as Scotland is a very odd shape.

When the evergreen yew grows so slowly and appears not to die, you can see how it might become a symbol of eternal life and the focus of religious rites. Just as the Christian calendar takes in festivals that derive from earlier beliefs, so perhaps the churchyards were sacred places before any Christian church was built or before the Christian faith arrived. Tree worship, the Tree of Life, Druids, Celts and even a tradition that Jesus' cross was made from yew...I'll never look at churchyards the same again.

The tree alone is a paradox: it looks like a conifer but it doesn't grow cones. Instead it has red berries in autumn - that's what 'baccata' means in the Latin name. If birds eat those berries, do they die? No, the fleshy part is edible but the seed inside (and every other part of the tree) is deadly. Apparently it takes between 50 and 100 grams/ 2 to 4 ounces to kill an adult and twice that for a horse. Pigs and cattle need to eat a lot more. The poison acts as a cardiac depressant, so death is due to heart failure. Life however may spring from an anti-cancer drug called Taxol, which is taken from the inner bark or cambium of the Pacific Yew. Herbalists and Native Americans have also treated rheumatism with yew, but don't try that at home.

One more loose end - why is the yew so good for shooting arrows? The formal answer is its high tensile strength. Bending a bow compresses the inner face of the wood, so it's better to spread that stress over a long bow. Hence the name 'longbow': it can be as tall as the person who holds it. The weapon was most valued in the 13th to 16th centuries with the Battle of Agincourt in 1415 being a famous example of its lethal effect.

The ancient yew trees we see in churchyards now were probably never used for warfare, because the best wood (the stave) comes from a straight trunk. You can't get it from a branch or a gnarled stem. When the English supply of useful trees ran out, yew staves were imported from Spain and the Alps. In those places too the yew became rare and expensive, so archers used White Ash for a practice bow and yew for matters of life and death. They also poisoned their arrow-heads with a liquid distilled from yew seeds. Modern longbows are made from up to three different woods laminated together or from carbon fibre.

If our ancestors treasured the yew, more recent folks have vandalised it. The tree at Fordingall is surrounded by a 6-foot wall and iron railings because Victorian souvenir-hunters were cutting so much of the wood. At Iffley, people have stripped bark from the trunk. At All Saints Church in Didcot, another old yew was deliberately set on fire. At St. Mary's, Cholsey, near Wallingford, an ancient yew died a natural death. It collapsed during a storm in 1990 and was found to be completely hollow.

That churchyard has another point of interest because it holds the grave of Agatha Christie, who lived near Wallingford and died 32 years ago. The church at Cholsey was founded in 984, so here's a mystery Hercule Poirot and Miss Marple might have solved. You too can ponder it at other churchyards. Which came first: the tree or the church? If the tree was first, how did it get there? Why was a church built nearby? Nobody can prove the answers of course, and the yew (a much older species than we are) is keeping its secrets.

John Gorrill

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