Taxus baccata

Taxus baccata, an evergreen tree from the Taxaceae family, is the original yew tree. To set it apart from related species, it is also called common yew, European yew, or, in North America, English yew. Its native range covers much of Eurasia and Northwest Africa, where it grows as a woodland tree. Every part of the plant except the fleshy aril is poisonous; these toxins can enter the body through inhalation, ingestion, or absorption through the skin.

The wood has long been valued for crafting longbows and musical instruments like lutes. Yews are commonly planted as ornamentals, hedges, or topiaries, especially in churchyards, where some specimens reach remarkable ages. Many theories explain this tradition, often linking the yew to death, immortality, and rebirth. Certain place names stem from the Proto-Celtic *eburos, though scholars disagree on whether this word actually referred to the yew.

**Taxonomy** Carl Linnaeus first described the species *Taxus baccata* in 1753 in his *Species Plantarum*. The name remains accepted despite 108 synonyms created by later taxonomists. Linnaeus chose the genus name *Taxus*, possibly from the Greek *toxon*, meaning bow. The word "yew" traces back through Old English and Proto-Germanic *iwo* to the Proto-Indo-European root *h₁eyHw-, which also produced Celtic forms like Old Irish *ēo* and Welsh *ywen*. *Baccata* is Latin for "bearing berries."

**Description** Yews are small to medium-sized evergreen trees, reaching up to 20 meters (66 feet) tall, with trunks up to 4 meters (13 feet) in diameter. The thin, scaly bark is reddish-brown and flakes off in small pieces aligned with the stem. The flat, dark green leaves are 1–4 cm (0.4–1.6 in) long and 2–3 mm (0.08–0.12 in) wide. They are arranged spirally on the stem, but the leaf bases twist so the leaves lie in two flat rows on either side of the stem—except on erect leading shoots, where the spiral is more obvious.

The seed cones are modified, each containing a single seed 4–7 mm (0.16–0.28 in) long, nearly surrounded by a fleshy scale that develops into a soft, bright red, berry-like aril. This aril is 8–15 mm (0.31–0.59 in) long and wide, open at the end, and matures 6 to 9 months after pollination. The aril is gelatinous and very sweet. Male cones are globose, 3–6 mm (0.12–0.24 in) in diameter, shedding pollen in early spring. Yews are mostly dioecious, with male and female cones on separate trees, though occasional individuals can be variably monoecious or change sex over time.

**Distribution** The yew is native to every European country except Iceland, as well as the Caucasus, Turkey, and eastward to northern Iran. Its range extends south to Morocco and Algeria in North Africa and into parts of Southwest and South Asia. A few populations exist in the Azores and Madeira archipelagos. Its northern limit in Scandinavia is set by frost sensitivity, and global warming is predicted to allow it to spread inland. It has been introduced elsewhere, including the United States.

**Habitat and Ecology** In central Europe, the richest yew populations grow in Swiss yew-beech woodlands on cool, steep marl slopes up to 1,200 meters (3,900 feet) in elevation in the Jura Mountains and Alpine foothills. In the UK, it thrives on steep chalk down slopes, forming extensive stands that invade grassland outside beech woods. In more continental European climates, it does better in mixed forests of conifers and broadleaf trees. Under its evergreen shade, no other plants can grow.

The species prefers steep, rocky, calcareous slopes. It rarely develops beyond saplings on acid soil under a forest canopy, but it tolerates a wide range of soil pH when planted by humans—such as in churchyards and cemeteries, where some of the largest and oldest trees in northwestern Europe are found. It grows well in well-drained soils, tolerating nearly any soil type, typically humus and base-rich soils, but also rendzina and sand soils if moisture is adequate. It can survive temporary flooding and moderate droughts. Its roots can penetrate extremely compressed soils, such as on rocky terrain and vertical cliff faces. It usually appears individually or in small groups in the understory, but forms stands throughout its range, especially on sheltered calcareous sites. It is extremely shade-tolerant and has the widest temperature range for photosynthesis among European trees, allowing it to photosynthesize in winter after deciduous trees have shed their leaves. It can grow under partial canopies of beech and other deciduous broadleaf trees, though it only becomes a large tree without such shade.

Birds eat the arils and disperse the hard, undamaged seeds in their droppings. Despite the toxins, some birds—like hawfinches, greenfinches, and great tits—extract and eat the kernels.

**Conservation** Historically, yew populations were gravely threatened by felling for longbows and by destruction to protect livestock from poisoning. It is now endangered in parts of its range due to intensive land use. The species is also harvested to meet pharmaceutical demand for taxanes. Trees are often damaged by browsing and bark stripping. Its thin bark makes it vulnerable to fire. Its toxicity protects against many insects, but the yew mite causes significant bud mortality, and fungi can kill seedlings.

Clippings from ancient UK specimens, including the Fortingall Yew, were taken to the Royal Botanic Gardens in Edinburgh to form a mile-long hedge. This "Yew Conservation Hedge Project" aims to preserve the DNA of *Taxus baccata*. In the early 2010s, the Forest Sciences Centre of Catalonia ran a conservation program to protect genetically endemic yew populations and preserve them from overgrazing and forest fires. As part of this program, the 4th International Yew Conference was held.