Yew – pretty, powerful, poisonous


The yew (Taxus baccata) is quintessentially British; a native evergreen tree, it has long been associated with churches, and in particular graveyards. It used to be commonplace to find a yew tree planted not far from the lychgate leading into a graveyard; indeed, the clergyman, and other church officials, used to wait underneath the yew tree for the arrival of the cortège. However, the veneration of the yew tree existed long before Christianity reached Britain. The Celtic tribes had strong religious beliefs based on nature, and their priests – the Druids – held many plants and trees sacred. According to the only texts available (Roman ones!), the druids held mistletoe and the oak tree sacred. Other writers claim that there is evidence that up to 20 tree species – including the yew – were regarded as holy, each having its assigned attributes, and even a character in the runic script called Ogham, which was the only written form of Celtic communication at the time. Because yew trees can live to an immense age (some say 2,000 years, some up to 4,000) they were regarded by the early occupants of the British Isles as ‘immortal’. The yew can generate new stems which form part of the outer ring of the trunk of the tree, even as the inner portions decay. Very often an extremely old yew will be hollow, and split, so that people can even stand inside (rather like the ‘Major Oak’ in Sherwood Forest, Nottinghamshire, where Robin Hood is said to have hidden).

The major problem with the yew is that it is extremely toxic to humans, and many grazing animals. Almost every single part of the tree is poisonous, from the spiny leaves to the bark and the seeds; the seeds are surrounded by a bright red, fleshy aril (a modified form of scale). The aril is the only part which is edible, but great care has to be exercised by the few birds and animals which attempt this, since the seed it contains is very toxic. Blackbirds (Turdus merula), mistle thrushes (Turdus viscivorus), greenfinches (Carduelis chloris) and linnets (Carduelis cannabina) are amongst those birds which eat the yew berries, and seem to be able to discard the seeds and the skin of the aril without swallowing them. There is evidence that squirrels can also consume the aril, by stripping it away from the seed. Despite the fact that yew is an excellent furniture wood (closegrained and free from insect damage) and fine for various utensils, great care has to be taken in working the wood, as even the dust can be lethal.

Perhaps the classic use of the yew, however, is the English longbow. Usually around six feet in length, in the hands of a highly trained archer this was the ultimate European battlefield weapon for around 100 years. As the French and their allies found out during the Hundred Years War (1337 – 1453), a shower of arrows from English longbows were utterly deadly. Indeed, even charges by mounted knights at the battle of Agincourt (1415) could not stand against such a barrage, and a mighty English victory ensued.

Despite the great toxicity of the yew (it contains an alkaloid toxin which attacks cardiac functioning), some great good has come from it. Yew bark – usually from the Pacific yew (Taxomyoes andreanae) can be processed to yield a substance called paclitaxel, otherwise known as the drug Taxol®. This has proven cytotoxic effects against certain cancers, including ovarian cancer and advanced gastric carcinoma (see, ‘Phase II study of Taxol® in patients with advanced gastric carcinoma’, J A Ajani et al: 1998, Cancer Journal from the Scientific American: Vol. 4 (4) pgs 269 – 274). Fortunately, the yew trees are no longer cut down to obtain the chemical compound, as the drug can be synthesised by other means!

Finally, not every culture regards the yew as a symbol of death, or ill-luck. In certain areas of my native Derbyshire, yew branches are brought into the house at Christmas (along with other evergreens), and are used to decorate window-frames. Also, the delightful folk custom of well dressing, which is prevalent throughout the Peak District, uses yew foliage to ‘frame’ some of the beautiful designs made from flower petals, seeds and other natural objects, pressed into damp clay.

The yew is a dangerous, yet complex part of the British landscape. Just when you think you know all there is to know about Taxus baccata, something pops up to surprise you (or yew!)

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One comment on “Yew – pretty, powerful, poisonous”

  1. You have used my copyright image for the Yew from my blog post WITHOUT prior permission! As such you are breaking Title 17, U.S. Code. Remove this IMMEDIATELY!!

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