Taxus baccata | Yew

Introduction

The yew (Taxus baccata) is a dark, slow-growing evergreen conifer with blood-red berries, a tree so long-lived that individual specimens in British and Irish churchyards may predate the buildings beside them. Intimately associated with churchyards and ancient woodland, it is also one of the most poisonous trees in Europe—nearly every part is toxic, except the red flesh around the seed. Its dense, springy timber made the medieval longbow, and its chemistry now yields cancer drugs.

Taxonomy

Taxus baccata is a conifer in the family Taxaceae, the yews, a small family distinct from the pine and cypress families. Its seeds are borne singly, each partly enclosed in a fleshy red cup called an aril, rather than in a woody cone. As a green plant it depends on Photosynthesis, and its flattened, dark, evergreen needles are arranged to pick up what little light reaches the woodland floor, letting it grow in deep shade where most trees cannot.

Physical Characteristics

Yew is a broadly conical tree, usually ten to twenty metres tall, with a massive, often fluted and irregular trunk that can reach several metres in diameter on ancient specimens. The bark is thin, reddish-brown, and peels in strips. The needles are flat, dark glossy green above and paler beneath, one to three centimetres long, arranged in two opposite rows along the shoots. Trees are usually either male or female; females bear the familiar soft, translucent red arils, each containing a single hard seed.

Habitat

Yew grows in woodland, on chalk and limestone scree and downland, in ravines, and in churchyards and parks, on well-drained soils from alkaline to slightly acidic. It is native across Europe, western Asia, and north Africa. It is exceptionally shade-tolerant and can survive beneath a closed canopy for decades, waiting for a gap. It also withstands exposure and cold, and old trees often occupy sites where little else will grow.

Diet

Yew is autotrophic, photosynthesising in its evergreen needles year-round in suitable weather. Its remarkable shade tolerance comes from needles that work efficiently at very low light levels, so it can persist on the woodland floor for years and accelerate when a gap opens. Water and minerals come from a wide, shallow root system, and like many woodland trees it partners with mycorrhizal fungi in the soil that improve nutrient uptake.

Reproduction

Male trees release clouds of yellow pollen from small cones in early spring, carried by wind to the tiny green female structures. After fertilisation the seed develops inside a fleshy red aril that ripens in late summer and autumn. Birds such as thrushes, waxwings, and blackbirds swallow the arils and pass the hard seeds intact, planting them far away. Yew also spreads by layering, and old trees often produce new trunks from low branches touching the ground.

Conservation

The species is not globally threatened and is widespread, though ancient wild yew woodland is rare and highly valued; some European yew woods are among the continent’s oldest protected habitats. Individual ancient trees are at risk from development, soil compaction around their roots, and heavy pruning. Because the foliage is poisonous, yew is also a serious hazard to livestock, and even small amounts of clippings can kill cattle and horses.

Fun Facts

• Individual yews in European churchyards are thought to be over a thousand years old.
• Almost every part of the tree is poisonous except the red flesh of the berry.
• The seed inside the red aril is the most toxic part of all.
• Its springy wood made the famous English longbow of the Middle Ages.
• Compounds from yew are used today to make important chemotherapy drugs.