Categories
Herbs & Plants

Taxus Brevifolia (Yew)


Botanical Name:
Taxus baccata
Family
: Taxaceae
Genus:
Taxus
Species:
T. brevifolia
Kingdom:
Plantae
Phylum:
Pinophyta
Class:
Pinopsida
Order:
Pinales


Common Names:
Yew, English yew, Common Yew

Other Names:Taxus brevifolia, Pacific Yew or Western Yew
Poisonous Parts: Leaves, seed and fruit.

Habitat :Taxus Brevifolia  is native to  Europe, incl Britain, from Scandanavia south and east to N. Africa, the Caucasus, Iran, Himalayas.   It grows in woods and scrub, usually on limestone. It sometimes forms pure stands in sheltered sites on chalk in the south-east and on limestone in the north-west.  

Description: It is a small to medium-sized evergreen tree, growing 10-15 m tall and with a trunk up to 50 cm diameter, rarely more. forming with age a very stout trunk covered with red-brown, peeling bark and topped with a rounded or wide-spreading head of branches; leaves spirally attached to twigs, but by twisting of the stalks brought more or less into two opposed ranks, dark, glossy, almost black-green above, grey, pale-green or yellowish beneath, 1/2 to 1 1/2 inches long, 1/16 to 1/12 inch wide. Flowers unisexual, with the sexes invariably on different trees, produced in spring from the leaf axils of the preceding summer’s twigs. Male, a globose cluster of stamens; female, an ovule surrounded by small bracts, the so-called fruit bright red, sometimes yellow, juicy and encloses the seed.

CLICK & SEE THE PICTURES
Bloom Color: Green, Yellow. Main Bloom Time: Early spring, Late spring, Mid spring. Form: Rounded.

It has thin scaly brown bark. The leaves are lanceolate, flat, dark green, 1-3 cm long and 2-3 mm broad, arranged spirally on the stem, but with the leaf bases twisted to align the leaves in two flat rows either side of the stem except on erect leading shoots where the spiral arrangement is more obvious.

The seed cones are highly modified, each cone containing a single seed 4-7 mm long partly surrounded by a modified scale which develops into a soft, bright red berry-like structure called an aril, 8-15 mm long and wide and open at the end. The arils are mature 6-9 months after pollination, and with the seed contained are eaten by thrushes and other birds, which disperse the hard seeds undamaged in their droppings; maturation of the arils is spread over 2-3 months, increasing the chances of successful seed dispersal. The male cones are globose, 3-6 mm diameter, and shed their pollen in early spring. It is mostly dioecious, but occasional individuals can be variably monoecious, or change sex with time.

No tree is more associated with the history and legends of Great Britain than the Yew. Before Christianity was introduced it was a sacred tree favoured by the Druids, who built their temples near these trees – a custom followed by the early Christians. The association of the tree with places of worship still prevails.

Many cases of poisoning amongst cattle have resulted from eating parts of the Yew.

Click to read about The Yew ,Sacred Tree of Transformation and Rebirth

Cultivation:
Landscape Uses:Espalier, Firewood, Hedge, Screen, Standard, Superior hedge, Specimen. A very easy plant to grow, it is extremely tolerant of cold and heat, sunny and shady positions, wet and dry soils, exposure and any pH[200]. Thrives in almost any soil, acid or alkaline, as long as it is well-drained. Grows well in heavy clay soils. Sensitive to soil compaction by roads etc. Very shade tolerant. Tolerates urban pollution.  In general they are very tolerant of exposure, though plants are damaged by severe maritime exposure. A very cold hardy plant when dormant, tolerating temperatures down to about -25°c. The fresh young shoots in spring, however, can be damaged by frosts. Plants are dioecious, though they sometimes change sex and monoecious trees are sometimes found. Male and female trees must be grown if fruit and seed is required. The fruit is produced mainly on the undersides of one-year old branches. A very long lived tree, one report suggests that a tree in Perthshire is 1500 years old, making it the oldest plant in Britain. Another report says that trees can be up to 4000 years old. It is, however, slow growing and usually takes about 20 years to reach a height of 4.5 metres. Young plants occasionally grow 30cm in a year but this soon tails off and virtually no height increase is made after 100 years. A very ornamental tree, there are many named varieties. Very resistant to honey fungus, but susceptible to phytopthera root rot. The bark is very soft and branches or even the whole tree can be killed if the bark is removed by constant friction such as by children climbing the tree. Plants produce very little fibrous root and should be planted in their final positions when still small. The fruit is greatly relished by thrushes. Special Features: Not North American native, All or parts of this plant are poisonous, Inconspicuous flowers or blooms.

Propagation:
Seed – can be very slow to germinate, often taking 2 or more years. It is best sown as soon as it is ripe in the autumn when it should germinate 18 months later. Stored seed may take 2 years or more to germinate. 4 months warm followed by 4 months cold stratification may help reduce the germination time. Harvesting the seed ‘green’ (when fully developed but before it has dried on the plant) and then sowing it immediately has not been found to reduce the germination time because the inhibiting factors develop too early. Prick out the seedlings into individual pots once they are large enough to handle and grow them on in pots in a cold frame. The seedlings are very slow-growing and will probably require at least 2 years of pot cultivation before being large enough to plant out. Any planting out is best done in late spring or early summer, after the last expected frosts. Cuttings of half-ripe terminal shoots, 5 – 8cm long, July/August in a shaded frame. Should root by late September but leave them in the frame over winter and plant out in late spring. High percentage. Cuttings of ripe terminal shoots, taken in winter after a hard frost, in a shaded frame.

Edible Uses:

Fruit – raw. Very sweet and gelatinous, most people find it delicious though some find it sickly. A number of people who like the flavour do not like the texture which is often described as being ‘snotty’. All other parts of this plant, including the seed, are highly poisonous. When eating the fruit you should spit out the large seed found in the fruit’s centre. Should you swallow the whole seed it will just pass straight through you without harm (UPDATE: this is probably not true: unfortunately, the digestive system of most mammals, including humans, is robust enough to break down the seeds. This will release the toxic taxanes. Birds are able to eat the whole “berry” because they cannot digest the seeds). If it is bitten into, however, you will notice a very bitter flavour and the seed should immediately be spat out or it could cause some problems. The fruit is a fleshy berry about 10mm in diameter and containing a single seed. Some reports suggest using the bark as a tea substitute, this would probably be very unwise.

Constituents: The fruit and seeds seem to be the most poisonous parts of the tree. An alkaloid taxine has been obtained from the seeds; this is a poisonous, white, crystalline powder, only slightly soluble in water; another principle, Milossin, has also been found.

Medicinal Uses:

The yew tree is a highly toxic plant that has occasionally been used medicinally, mainly in the treatment of chest complaints. Modern research has shown that the plants contain the substance ‘taxol’ in their shoots. Taxol has shown exciting potential as an anti-cancer drug, particularly in the treatment of ovarian cancers. Unfortunately, the concentrations of taxol in this species are too low to be of much value commercially, though it is being used for research purposes. This remedy should be used with great caution and only under the supervision of a qualified practitioner. See also the notes below on toxicity. All parts of the plant, except the fleshy fruit, are antispasmodic, cardiotonic, diaphoretic, emmenagogue, expectorant, narcotic and purgative. The leaves have been used internally in the treatment of asthma, bronchitis, hiccup, indigestion, rheumatism and epilepsy. Externally, the leaves have been used in a steam bath as a treatment for rheumatism. A homeopathic remedy is made from the young shoots and the berries. It is used in the treatment of many diseases including cystitis, eruptions, headaches, heart and kidney problems, rheumatism etc. Ingestion of 50-100g of needles can cause death.

(In homoeopathy a tincture of the young shoots and also of the berries is used in a variety of diseases: cystitis, eruptions, headache and neuralgia, affections of the heart and kidneys, dimness of vision, and gout and rheurmatism. – EDITOR) .

The chemotherapy drug paclitaxel, used in breast, ovarian and lung cancer treatment, is derived from Taxus brevifolia. Over-harvesting for production of this drug has resulted in the Pacific Yew becoming a rare species, despite the fact the drug can be produced semi-synthetically from cultivated yews. Pharmaceutical use of closely-related wild yew species in India and China threatens some of those species as well.

Click to read Taxol, an Anticancer Drug, is found in the Pacific Yew tree

Other Uses:  
Very tolerant of trimming, this plant makes an excellent hedge. The plants are often used in topiary and even when fairly old, the trees can be cut back into old wood and will resprout. One report says that trees up to 1000 years old respond well to trimming. A decoction of the leaves is used as an insecticide. Some cultivars can be grown as a ground cover when planted about 1 metre or more apart each way. ‘Repandens’ has been recommended. Wood – heavy, hard, durable, elastic, takes a good polish but requires long seasoning.  Highly esteemed by cabinet makers, it is also used for bows, tool handles etc. It makes a good firewood. The wood is burnt as an incense

Known Hazards :  All parts of the plant, except the flesh of the fruit, are highly poisonous, having a paralyzing affect on the heart. Poisoning symptoms are dry mouth, vomiting, vertigo, abdominal pain, dyspnoea, arrhythmias, hypotension & unconsciousness.

Disclaimer:
The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplements, it is always advisable to c

Yew may refer to various other species, click to read about them:
Any of various coniferous trees and shrubs in the genus Taxus:
European Yew or Common Yew (Taxus baccata)
Canadian Yew (Taxus canadensis)
Chinese Yew (Taxus chinensis)
Japanese Yew (Taxus cuspidata)
Florida Yew (Taxus floridana)
Mexican Yew (Taxus globosa)
Sumatran Yew (Taxus sumatrana)
Himalayan Yew (Taxus wallichiana)
Any of various coniferous plants in the families Taxaceae and Cephalotaxaceae:
White-berry Yew (Pseudotaxus chienii)
New Caledonian Yew or Southern Yew (Austrotaxus spicata)
Catkin-yew (Amentotaxus sp.)
Plum-yew (Cephalotaxus sp.)
Any of the various coniferous plants in the family Podocarpaceae which are superficially similar to other yews:
Prince Albert’s Yew (Saxegothaea conspicua)
Plum-yew (Prumnopitys sp.)

Fortigall Yew

Resources:
http://botanical.com/botanical/mgmh/y/yew—08.html
http://en.wikipedia.org/wiki/Taxus_brevifolia

.http://www.pfaf.org/user/plant.aspx?LatinName=Taxus+baccata

css.php