Botanical Name: Taxus bacatta
Species: T. baccata
Common Names: Common yew, English yew,or European yew.
Habitat: Taxus baccata is native to all countries of Europe (except Iceland), the Caucasus, and beyond from Turkey eastwards to northern Iran. Its range extends south to Morocco and Algeria in North Africa. A few populations are also present in the archipelagos of the Azores and Madeira. The limit of its northern Scandinavian distribution is its sensitivity to frost, with global warming predicted to allow its spread inland. It has been introduced elsewhere, including the United States.
Taxus bacatta is small to medium-sized evergreen tree, growing 10–20 m (35–65 ft) (exceptionally up to 28 m or 92 ft) tall, with a trunk up to 2 m (6 ft 7 in) (exceptionally 4 m or 13 ft 1 in) in diameter. The bark is thin, scaly brown, and comes off in small flakes aligned with the stem. The leaves are flat, dark green, 1–4 centimetres (1?2–1+1?2 in) long, 2–3 mm (3?32–1?8 in) broad, and arranged spirally on the stem, but with the leaf bases twisted to align the leaves in two flat rows on either side of the stem, except on erect leading shoots where the spiral arrangement is more obvious. The leaves are poisonous.
The seed cones are modified, each cone containing a single seed, which is 4–7 mm (3?16–1?4 in) long, and partly surrounded by a fleshy scale which develops into a soft, bright red berry-like structure called an aril. The aril is 8–15 mm (5?16–9?16 in) long and wide and open at the end. The arils mature 6 to 9 months after pollination, and with the seed contained, are eaten by thrushes, waxwings and other birds, which disperse the hard seeds undamaged in their droppings. Maturation of the arils is spread over 2 to 3 months, increasing the chances of successful seed dispersal. The seeds themselves are poisonous and bitter, but are opened and eaten by some bird species, including hawfinches, greenfinches, and great tits. The aril is not poisonous; it is gelatinous and very sweet tasting. The male cones are globose, 3–6 mm (1?8–1?4 in) in diameter, and shed their pollen in early spring. Yews are mostly dioecious, but occasional individuals can be variably monoecious, or change sex with time.
Grow yew in moist but well-drained soil in full sun to full shade. Water well as the plant establishes and then you shouldn’t need to water again – yews do best in slightly drier soils as they can succumb to root rot in damper conditions. Trim established hedges in summer. Standard yew trees need very little care.
Prepare the soil by digging it over and incorporating well-rotted manure or garden compost. Yew trees are available as potted or bare-root plants. Bare-root plants are cheaper to buy, especially when planting a hedge. Plant in autumn or spring, spacing hedging plants 60cm apart. Firm gently around the rootball and water well. Water during dry spells in the first year, until established.
Yew does well in containers and makes an ideal shrub for a formal display such as on either side of a front door. Additional watering is necessary in pots as the roots have much less soil to search for moisture.
Taxus baccata ’Green Diamond’ is currently propagated by grafting in Western European ornamental tree nurseries, which is however a costly and slow propagation method. As part of our work, we set the aim to work out the propagation method for Taxus baccata ’Green Diamond’ by cuttings. As part of our work, we examined the propagation of Taxus baccata ’Green Diamond’ by cutting in various plant growth mediums with the application of root stimulants in different concentrations.
Certain compounds found in the bark of yew trees were discovered in 1967 to have efficacy as anti-cancer agents. The precursors of the chemotherapy drug paclitaxel (taxol) were later shown to be synthesized easily from extracts of the leaves of European yew,] which is a much more renewable source than the bark of the Pacific yew (Taxus brevifolia) from which they were initially isolated. This ended a point of conflict in the early 1990s; many environmentalists, including Al Gore, had opposed the destructive harvesting of Pacific yew for paclitaxel cancer treatments. Docetaxel can then be obtained by semi-synthetic conversion from the precursors.
Yew wood was historically important, finding use in the Middle Ages in items such as musical instruments, furniture, and longbows. The species was felled nearly to extinction in much of Europe. In the modern day it is not considered a commercial crop due to its very slow growth, but it is valued for hedging and topiary. When grown as a hedge, yew provides dense shelter for birds. Its fruit is eaten by birds and small mammals such as squirrels and dormice. Its leaves are a foodplant for the caterpillars of the satin beauty moth.
All parts of the yew tree are poisonous, but it’s the berries (in particular the seeds) that contain the highest concentrations of taxine alkaloids. Birds and grey squirrels are able to eat the fruit, either eating only the flesh or passing the seed intact through their digestive system. However, it’s important to ensure that you, your children and pets do not to consume yew berries or needles, as they could cause severe illness if eaten in sufficient quantities. Yew poisoning symptoms can include:
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.