The oldest tree in Britain is undergoing a sex-change, according to stumped botanists.

The 5,000 year old Fortingall Yew in Perthshire has long been considered male because it produced pollen, whereas female varieties of the tree bear berries.

Yet “three ripe, red berries” blossomed on one of the elderly yew’s upper branches last year — shocking experts.

Dr. Max Coleman, who works at the Royal Botanic Garden Edinburgh and discovered the berries, told the BBC that gender bending trees are not unprecedented– but “not fully understood.”

The berries have been collected for study.

It is difficult to determine the age of ancient yews, as their yearly growth rings rot away.

The Fortingall Yew is said to be one of the oldest living organisms in Europe. According to local legend, Roman prefect Pontius Pilate was born in the tree’s shadow.