The Survival of Yew Trees in Britain
How Does Britain’s Oldest Living Organism Keep Going?
Sep 7, 2008
The native British yew is Taxus baccata. The leaves and seeds are toxic.
Oldest Living Things in Britain
Britain is home to about a thousand living creatures born in the 1500s, some born before the Normans invaded in 1066. One or two are contemporaries of Christ. They're yew trees.
How Yews Live So Long
Yews have effective survival strategies. Secondary shoots grow at the base and merge with the main trunk, giving the tree a ridged appearance. When the main trunk decays the new trunks keep the tree alive. Branches can put down roots into the decaying central trunk, literally growing new life from its own decay, or can take root in surrounding soil. The roots can also send up new shoots, and the tree's slow decay gives them time to establish.
Yew Tree Toxins
Yews have very few parasites, perhaps because most parts of the tree are toxic. Taxine, ephedrine, and taxiphyllin are all present. Only the fleshy fruit is safe to consume, and yew berries look unappealing to humans. The seeds are toxic, the leaves more so - 50-100 grams of chopped yew foliage is considered a fatal adult dose.
Human poisoning is rare. According to Fred Hageneder of the Ancient Yew Group, a study published in 1992 found 10 fatal cases of human yew poisoning since 1961, none accidental. (Van Ingen, G., Visser, R., Peltenburg, H., Van Der Ark, A.M. & Voortman, M. (1992) Sudden unexpected death due to Taxus poisoning. A report of five cases, with review of the literature. Forensic Science International, 56, 81-87.) Even the dust of yew wood can be toxic; anyone working with yew should ensure the area is well ventilated and wear a respirator.
Medieval Commercial Exploitation
Yew trees grow all over the United Kingdom and Ireland, although very old yews are rare in the Eastern counties of England. They are also widespread in France and Spain. The oldest trees in Britain are found in churchyards, religious sites, and remote areas, where they have grown undisturbed for centuries. There were once huge numbers of yews in forests all over the country, but most of these did not grow very large or survive very long because of competition for light and space, and industrial tree felling.
Yew was the vital component of one of the most advanced weapons of the Middle Ages, the English longbow. From the early 13th to the late 16th century the kings of England used so much yew for military purposes that they exhausted the forests of Britain and Ireland and had to import yew from all over Europe. An Order in Council of Elizabeth I dated October 26, 1595, replacing military longbows with firearms, was partly triggered by the European yew famine, proving that over-exploitation of natural resources is nothing new.
Dealing with a Damaged Yew Tree
Yews are lost in two main ways - through natural disaster or human intervention. They have been felled to allow new building, chopped up because they have fallen or been damaged, and even attacked by souvenir hunters.
If a yew tree falls or is damaged, the best thing to do is nothing at all. Yews can be completely flat on the ground, yet continue to thrive, as long as some roots remain in the soil. Simply make any loose branches or sections safe and leave the tree alone. If a yew has died completely, leave the stump in place if possible. You may not see much activity for a while, but the tree could establish new shoots in any of the ways described above, making another yew for future generations to enjoy.
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