English: Thousand-year-old yew tree. This is one of two ancient yew trees situated within the "Plaisance" (a walled garden beside Kelburn Castle). The trees are certified as over one thousand years old.

Note, though, that dating yew trees is not a simple matter of counting rings: "after 400 or 500 years almost all yews begin to lose their heartwood and become hollow, making dating by ring-counts impossible. They also enter long periods of suspended growth, when they put on virtually no extra girth at all." [Richard Mabey, "Flora Britannica"]

The Common Yew, Taxus baccata, is usually a dioecious species: there are separate male and female trees. One of the trees in the Plaisance is a male, while the other is a female.

The nearby castle has been continuously inhabited by the same family (Boyle) since the first Norman keep was built on the site in about 1200, but their ancestors (then surnamed "de Boyville") arrived in Britain with William the Conqueror in 1066. However, these venerable trees pre-date even that arrival.

Particularly ancient yew trees are often found in churchyards (the Fortingall Yew, located in a churchyard, is among Europe's oldest known trees: 847537). It may be that, in pre-Christian tradition, their poisonous seeds made them symbols of death, while their longevity and their evergreen foliage made them, at the same time, fitting symbols of immortality.

In 2002, the Kelburn Yews were included in the Forestry Commission's list of "100 Heritage Trees of Scotland".