Yew (Taxus baccata)

The Yew tree is a coniferous tree which can be found all over Europe, Northwest Africa and into central Asia. Its normal form is of a smallish tree up to 25 meters tall with a thin scaly brown bark which sheds in small flakes. The leaves are a flat dark green; they are poisonous, as are most parts of the plant except the reddish fruit which surrounds the seeds. The leaves are so poisonous that even when dried they are still  dangerous especially to horses with cattle being more tolerant of the taxine poison they contain, death comes rapidly from heart failure following respiratory problems and muscle tremors.

In traditions several celtic leaders used Yew to poison themselves rather than surrender to the Romans and Yew trees can be traditionally found in British Church yards. Since the trees are very long lived and slow growing many actually predate the churches they are in the grounds of. Many suggest they were used by Pagan faiths to make ancient burial sites as a symbol of long life and more pragmatically as they would have discouraged cattle from grazing on the burial site; it was common for early Christian churches to be built on existing pagan sites as part of establishing religious dominance. In warfare the Yew was associated with the English and Welsh longbow as the heartwood made a very good material for longbow making, although much of the wood would be discarded and the trade lead to a massive reduction in the numbers of native Yew trees during the Middle Ages. Medicinally a chemotherapy drug Pacilitaxel can be synthesized from a extract from the common Yew

What Culpepper says

Description. It grows to be an irregular tree, spreading widley into branches. The leaves are long, narrow, and placed with a beautiful regularity. The flowers are yellowish, and the berries are surrounded with a sweet juicy matter.

Place. We have it growing in woods, and in the gardens, but its usual ancient residence is the church-yard: conjectures upon the antiquity and origin of which plantatin, has brought forth much pedantic nonsense; Gray observes this in the Grave, a Poem, when he says,
"Well do I know thee by thy trusty Yew,
"Shading for years thy gloomy church-yard view;
"Cheerless, unsocial plant, that loves to dwell
"Where scatter'd bones man's dissolution tell".

Government and virtues. This is a tree of Saturn. The leaves are said to be poisonous; but the wood, if it grew with more regularity would be very valuable. This tree, though it has no place among the physical plants, yet does it not deserve (at least in our climate) so bad a character as the ancients give it, viz. a most poisonous vegetable, the berries of which threaten present death to man and beast that eat them; many in this country having eaten them and survived. However that be, it has very powerful poisonous qualities, that rise by distillation. In this form it is the most active vegetable poison known in the whole world, for in a very small dose it instantly induces death without any previous disorder; and its deleterious power seems to act entirely upon the nervous system, and without exciting the least inflammation in the part to which it more immediately enters. It totally differs from opium and all other sleepy poisons, for it does not bring on the lethargic symptoms, but more effectually penetrates and destroys the vital functions, without immediately affecting the animal. These observations would not have been made, or the article inserted here, but to caution against any rash application of it, for though it is sometimes given useful in obstructions of the liver and bilious complaints, those experiments seem too few to recommend it to be used without the greatest caution. The deleterious qualities of laurel-water are more than equalled by this.