Taxus baccata

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 Taxus baccata subsp. var.  Common Yew, English Yew
Taxus baccata (European Yew)
Habit: tree
Height: to
Width: to
50ft 25ft
Height: warning.png"" cannot be used as a page name in this wiki. to 50 ft
Width: warning.png"" cannot be used as a page name in this wiki. to 25 ft
Lifespan:
Origin:
Poisonous: parts are toxic
Bloom:
Exposure: sun
Water:
Features: evergreen, edible, fruit
Hidden fields, interally pass variables to right place
Minimum Temp: °Fwarning.png"°F" is not a number.
USDA Zones: 5 to 10
Sunset Zones:
Flower features:
Taxaceae > Taxus baccata var. , L.



Taxus baccata is a conifer native to western, central and southern Europe, northwest Africa, northern Iran and southwest Asia.[1] It is the tree originally known as yew, though with other related trees becoming known, it may be now known as the common yew, or European yew.

Description

It is a small- to medium-sized evergreen tree, growing 10 - 20 m (exceptionally up to 28 m ) tall, with a trunk up to 2 m (exceptionally 4 m ) diameter. The bark is thin, scaly brown, coming off in small flakes aligned with the stem. The leaves are lanceolate, flat, dark green, 1 - 4 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 leaves are highly poisonous.[1][2]

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, waxwings 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 seeds themselves are extremely poisonous and bitter, but are opened and eaten by some bird species including Hawfinches[3] and Great Tits.[4] The aril is not poisonous, and is gelatinous and very sweet tasting. 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.[1][2][5]

It is relatively slow growing, but can be very long-lived, with the maximum recorded trunk diameter of 4 metres probably only being reached in about 2,000 years. The potential age of yews is impossible to determine accurately and is subject to much dispute. There is rarely any wood as old as the entire tree, while the boughs themselves often hollow with age, making ring counts impossible. There are confirmed claims as high as 5,000-9,500 years,[6] but other evidence based on growth rates and archaeological work of surrounding structures suggests the oldest trees (such as the Fortingall Yew in Perthshire, Scotland) are more likely to be in the range of 2,000 years.[7][8] Even with this lower estimate, Taxus baccata is the longest living plant in Europe.


Standard Cyclopedia of Horticulture

Taxus baccata, Linn. Tree, attaining 60 ft., with a usually short trunk, occasionally 8 ft. or more in diam.: bark reddish, flaky, deeply fissured in old trees: branches spreading, forming a broad, low head; branchlets somewhat pendulous: lvs. 2-ranked, linear and usually falcate, shortly acuminate, with prominent midrib, dark green above, pale beneath, 3/4 – 1 1/4 in. long or shorter in some varieties: fr. 1/3 – 1/2 in. across, with almost globose disk, about a third longer than the broadly ellipsoid brown seed 1/4 in. long. Eu. and N. Afr. to Himalayas.—Many garden forms have originated in cult.; the following are the most important: Var. adpressa, Carr. (T. parvifolia, Wender. T. brevifolia, Hort., not Nutt. T. tardiva, Laws. T. baccata tardiva, Pilger). Shrub or low tree of irregular habit, with long spreading branches: lvs. oblong, obtusish, mucronulate, 1/3 – 1/2 in. long: disk of fr. shorter than the seed. Very distinct form. Var. adpressa erecta, Nichols. (var. adpressa stricta, Beissn.), has the foliage of the preceding, but erect branches forming a columnar bush. Var. aurea, Carr. (var. elvastonensis aurea, Beissn.). Lvs. golden yellow, more brightly colored at the tips and margin. This form has proved hardier than the type in New England. Var. argentea, Loud. (var. elegantissima, Hort.). Lvs. striped straw-yellow or sometimes whitish. Var. Dovastonii, Loud. Branches wide-spreading, nodding at the tips: lvs. dull green, short and abruptly mucronulate. G. 3:89. A very handsome form. Var. Dovastonii aureo-variegata, Beissn., is a form with the lvs. variegated with yellow. Var. erecta, Loud. (var. stricta, Hort.). Bushy form, with slender, upright branches and branchlets: lvs. narrower and smaller than in the type. Var. ericoides, Carr. (var. microphylla, Hort.). Dwarf form, with slender branches and small and very narrow, pointed leaves. Var. fastigiata, Loud. (T. hibernica, Hort.). Strictly fastigiate form, with stout crowded upright branches and branchlets: lvs. spirally arranged around the branches, dark glossy green. One of the most desirable evergreens of columnar habit for formal gardens. Var. fastigiata variegata, Carr. Less vigorous and more tender: lvs. marked yellowish white. Var. fastigiata aurea, Standish. Young growth golden yellow. Var. Fisheri, Hort. Some of the lvs. deep yellow, others green. Var. glauca, Carr. Vigorous form, with longer and narrower lvs. dark green above and with a glaucous bluish tint beneath. Var. Jacksonii, Gord. (var. pendula, Hort.). Branches spreading, pendulous at the tips, with more or less incurved lvs. Var. luteo-baccata, Pilger (var. fructu luteo, Loud.). With yellow fr. Var. procumbens, Loud. Prostrate shrub, with elongated and much ramified branches. Var. repandens, Hort. A low form with long wide-spreading branches and dull bluish green lvs. Var. Washingtonii, Beissn. Vigorous form, with longer lvs., partly colored golden yellow.


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Cultivation

An evergreen Tree growing to 15m by 10m at a slow rate.

It is hardy to zone 6 and is frost tender. It is in leaf all year, in flower from March to April, and the seeds ripen from September to November. The flowers are dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required) and are pollinated by Wind. The plant is not self-fertile. It is noted for attracting wildlife.

The plant prefers light (sandy), medium (loamy) and heavy (clay) soils, requires well-drained soil and can grow in heavy clay soil. The plant prefers acid, neutral and basic (alkaline) soils and can grow in very acid and very alkaline soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It requires dry or moist soil and can tolerate drought. The plant can tolerates strong winds but not maritime exposure. It can tolerate atmospheric pollution.

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[1, 11, 200]. Grows well in heavy clay soils. Sensitive to soil compaction by roads etc[186, 200]. Very shade tolerant[17, 81]. Tolerates urban pollution[200]. In general they are very tolerant of exposure, though plants are damaged by severe maritime exposure[K]. A very cold hardy plant when dormant, tolerating temperatures down to about -25°c[200]. The fresh young shoots in spring, however, can be damaged by frosts[186, K]. Plants are dioecious, though they sometimes change sex and monoecious trees are sometimes found[81, 186]. Male and female trees must be grown if fruit and seed is required[K]. The fruit is produced mainly on the undersides of one-year old branches[200]. A very long lived tree[1, 7, 11, 185], 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[11]. It is, however, slow growing and usually takes about 20 years to reach a height of 4.5 metres[186]. Young plants occasionally grow 30cm in a year but this soon tails off and virtually no height increase is made after 100 years[185]. A very ornamental tree, there are many named varieties[200]. Very resistant to honey fungus[8, 88, 200], but susceptible to phytopthera root rot[81, 88]. 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[186]. Plants produce very little fibrous root and should be planted in their final positions when still small[200]. The fruit is greatly relished by thrushes[186].

Propagation

Seed - can be very slow to germinate, often taking 2 or more years[78, 80]. 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[113]. 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[80]. 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[K]. 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[78]. High percentage[11]. Cuttings of ripe terminal shoots, taken in winter after a hard frost, in a shaded frame[113].

Pests and diseases

Varieties

Gallery

References

  1. 1.0 1.1 1.2 Rushforth, K. (1999). Trees of Britain and Europe. Collins ISBN 0-00-220013-9.
  2. 2.0 2.1 Mitchell, A. F. (1972). Conifers in the British Isles. Forestry Commission Booklet 33.
  3. http://wbrc.org.uk/WorcRecd/Issue%2020/hawfinch1.htm
  4. http://www.bto.org/gbw/PDFs/FocusOn/Focus_GRETI.pdf
  5. Dallimore, W., & Jackson, A. B. (1966). A Handbook of Coniferae and Ginkgoaceae 4th ed. Arnold.
  6. Lewington, A., & Parker, E. (1999). Ancient Trees: Trees that Live for a Thousand Years. London: Collins & Brown Ltd. ISBN 1-85585-704-9
  7. Harte, J. (1996). How old is that old yew? At the Edge 4: 1-9. Available online.
  8. Kinmonth, F. (2006). Ageing the yew - no core, no curve? International Dendrology Society Yearbook 2005: 41-46.

External links

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