The black yew or common yew (Taxus baccatalisten)) is a conifer that can be found in the northern mountain systems of the Iberian Peninsula. Characteristically, it has linear leaves, resembling needles, arranged in two opposite rows.
When the mature seed appears surrounded almost entirely by a ring or fleshy spheroid, translucent red in color, which is known as an aril.
The yew is a truly unique tree, in which the branches grow almost from the base ending in fine, pointed leaves, to which must be added that its trunk is empty.
In all parts of the tree, except the arils of the seeds, we can find a poisonous substance called taxin. It is an alkaloid capable of causing gastrointestinal irritation in our body and harmful effects on the cardiovascular system.
Taxin is a very pernicious substance, it is estimated that the liquid resulting from the cooking of 50-100 g of yew leaves would be enough to kill a human being.
From ancient Egypt to Numantia
For centuries the yew was surrounded by a halo of mysticism and its image was associated both with Life, its leaves were placed at the door of houses, and with Death, it was planted in cemeteries. Its harmful effect was already known in ancient times. Apparently the Numantines, back in 133 a. C., resorted to yew to carry out a collective suicide and avoid falling under the Roman yoke.
However, there are other European places where the yew is part of the tradition and not necessarily because of its lethal effects. Thus, there is an Irish legend that states that to marry a maiden it was necessary for the suitor to carry a branch of holly, a flower of marigold and crimson berries of yew.
It is also said that the bow of Robin Hood, the hero who led a revolt in Sherwood Forest, was made of yew wood. Precisely the same material with which some sarcophagi were made in ancient Egypt.
Few animals are free from the toxicity of the yew, which represents a serious problem to germinate and, therefore, to perpetuate their genes, which is why these trees have to be very long-lived to the point that some specimens can live for a thousand years.
For example, the Community of Madrid has, among its unique trees, the Barondillo de Lozoya yew, which is between 1,500 and 1,800 years old.
An ally against tumors
Etymologically, the name of these trees is related to badgers, a mammal of the mustelid family that make their intricate burrows among their roots.
For centuries, attempts have been made to compensate for the bad press of yew trees by seeking therapeutic remedies. At the time of Emperor Claudius, yew sap extract was recommended as an antidote to snakebite and in the Renaissance it was considered, at low doses, as antirheumatic, antimalarial and antiabortive.
In spite of everything, it was in the eighties of the last century that it acquired some notoriety in the field of medicine when some studies appeared stating that a drug (taxol) with anticancer properties could be obtained from yew bark. . At the moment there are more than ten different types of cancers that are effectively treated with this type of compound, which is manufactured synthetically without having to cut down the yew trees.