Additional notes (click to expand)
Taxus baccata is thought to be the longest living plant in Europe with estimated ages between 2000 and 4000 years. However, no one can determine the exact ages as the trunk hollows with age, making a ring count impossible. This does not make the plant unstable though as once it reaches a certain size, new shoots appear at the base and grow, fusing into the main truck and acting like buttresses.
A spreading dwarf Yew with bright golden-yellow which grows to form a compact mound of dense foliage. This slow growing conifer needs little or no pruning. Unlike many of the gold varieties, this will not scorch if planted in the full sun. 60cm high. Grow in any well-drained, fertile soil, including chalky or acid soils, in sun or deep shade. Insert semi-ripe cuttings in later summer or early autumn; take cuttings from strongly upright shoots (except for prostrate cultivars) otherwise they make not from a strong leading shoot. Graft cultivars in early autumn. Resistant to most diseases, except Phytophora root rot. May be damaged by tortrix moth caterpillars, vine weevil, and yew scale.
Brickell, C. (2003). A-Z Encyclopedia of Garden Plants. Dorling Kindersley. p.1026
POM – Taxol
Although regarded as poisonous since Theophrastus, Gerard and his school friends used to eat the red berries (they are technically called 'arils') without harm. Johnson clearly ate the fleshy arils and spat out the seed, which is as poisonous as the leaves. It is a source of paclitaxel (Taxol), an important chemotherapeutic agent for breast and other cancers. It was first extracted from the bark of T. brevifolia, the Pacific yew tree, in 1966. About 1,100 kg of bark produces 10 g of Taxol, and 360,000 trees a year would have been required for the needs of the USA – an unsustainable amount. In 1990 a precursor of Taxol was extracted from the needles of the European yew so saving the Pacific trees. It is now produced in fermentation tanks from cell cultures of Taxus. Curiously, there is a fungus, Nodulisporium sylviforme, which lives on the yew tree, that also produces Taxol. Because Taxol stops cell division, it is also used in the stents that are inserted to keep coronary arteries open. Here it inhibits – in a different way, but like anti-fouling paint on the bottom of ships – the overgrowth of endothelial cells that would otherwise eventually block the tube. The economic costs of anticancer drugs are significant. Paclitaxel ‘Taxol’ for breast cancer costs (2012) £246 every 3 weeks; Docetaxel (synthesised from paclitaxel) for breast, ovarian and other cancers costs up to £900 every three weeks; Cabazitaxel (a further synthetic) for prostate cancers costs £3,698 every 3 weeks and because of the cost is only licensed to be used in the UK after other treatments fail. Doxyrubicin (cost £915) from a bacteria, Streptomyces peucitius, is the main breast cancer drug now (2013).
Oakeley, Dr. Henry F. (2013). Wellcome Library notes. link
Mitotic inhibitors. Paclitaxel for breast cancer is extracted from the leaves; docetaxel for breast, ovarian and other cancers; and cabazitaxel for prostate cancers are synthesised from this. See Taxus baccata 'Fastigiata' for other properties.
Oakeley, Dr. H.F. (2013). Medicines from RCP plants label list 5-2013.docx.
Trees are feminine in Latin, so while Taxus has a masculine ending (-us), its specific name, baccata, agrees with it in gender by having a female ending (-a). In Latin, baccata means 'having fruits with a pulpy texture.'
Stearn, W.T. (1996). Dictionary of Plant Names for Gardeners. Cassell. p.58
Ancient Celts poisoned arrows tips and spears with Taxus extracts.
Wink, Michael & Ben-Erik van Wyk (2008). Mind-Altering and Poisonous Plants of the World. Timber Press
Yew wood possesses high elasticity and toughness. It made Anglo-Saxon longbows, the most dreaded long-range weapon of the Middle-Ages that had unparalleled penetrating power. Archers had to develop a tractive force of 85kg when drawing their bows. During the battle of Agincourt in 1415, a large portion of the French aristocracy perished in the rain of arrows unleashed from the English longbows, despite the armour the French wore when they charged.
Petersen, F. (2012). Physic Garden Medicinal Plant Guide. Novartis Pharma AG. p.133
Taxol is a taxane diterpene, 'a highly functional molecule possessing esters, epoxides, hydroxyls. amide, ketone groups and unsaturation. It has large numbers of chiral centres...'
Heinrich, Michael, Barnes, Joanne, Gibbons, Simon, Williamson, Elizabeth M. (2013). Fundamentals of Pharmacognosy and Phytotherapy. Churchill Livingstone Esevier.
The bark, needles and fruit (seed) of all species of yew contain a family of related alkaloids collectively called Taxines of which the most important are Taxine A and Taxine B, and Paclitaxel, the important anticancer drug popularly called Taxol and available as an anticancer drug under the trade name TAXOL®. Taxine B is responsible for most of the toxicity of yew as it is a potent and relatively cardio-selective calcium channel blocker.
Christina R. Wilson, John-Michael Sauer 1, Stephen B. Hooser. Toxicon 39 (2001), Taxines: a review of the mechanism and toxicity of yew (Taxus spp. ) alkaloids. p.175±185
"The Yew Tree, as Galen reporteth, is of a venemous qualities, and against man's nature. Dioscorides writeth ...that the yew is very venemous to be taken inwardly, and that if any doe sleepe under the shadow thereof it causeth sickness and oftentimes death, Morevoer, they say that the fruit thereof being eatenis not only dangerous and deadly unto man [but also birds].... Theophrastus saith that ... labouring beasts do die if they do eat of the leqaves, but such cattle as chew their cud receive no hurt at all thereby'. Gerard notes that he and his school friend ate the berries and slept under yew trees without being poisoned, but the fleshy aril round the seeds is said to be harmless, and only the seed is poisonous, so presumably he spat the seed out. Theophrastus's observations re cattle (circa 340BCE) are repeated in more modern texts.
Gerard, J. (1975). The Herbal or General History of Plants. New York: Fascimile Dover Publications Inc . p.1371
All parts (but not the arils) are highly toxic if ingested. Cardiotoxic.
Eating the needles or fruit (seeds) causes primarily slowing and weakening of the heart and inhibition of intestinal movements. The result is weakness, vomiting and diarrhoea, broadening of the ECG, disorders of intracardiac conduction and finally death mainly due to hypotension, seizures and ventricular dysrhythmias. The LD50 (fatal dose) of needles is about 0.7-2g/kg in most mammals depending on age and weight. It is some 8-times less toxic in the chicken.
Ondřej Piskač A, Jan Stříbrný, Hana Rakovcová, Martin Malý “Cardiotoxicity of yew“ c o r e t v a s a. 5 7 ( 2 0 1 5 ) ,e 2 3 4 – e 2 3 8
- Africa, Northern Africa, Algeria
- Africa, Northern Africa, Morocco
- Asia-Temperate, Caucasus
- Asia-Temperate, Western Asia, Iran
- Asia-Temperate, Western Asia, Turkey
- Europe, Eastern Europe, South European Russia
- Europe, Eastern Europe, Ukraine
- Europe, Middle Europe, Austria
- Europe, Middle Europe, Germany
- Europe, Southeastern Europe, Italy
- Europe, Southeastern Europe, Yugoslavia
- Europe, Southwestern Europe, France
- Europe, Southwestern Europe, Portugal
- Europe, Southwestern Europe, Spain
Taxus baccata L. 'Summergold'Family: TAXACEAE
Species: baccata L.
Distribution summary: Eurasia
Hardiness: H5 - Hardy; cold winter
Garden status: Currently grown
Garden location: Plants of the World (C)
Flowering months: March, April
Reason for growing: Medicinal, other use, toxic, prescription only medicine