Finnish Tundra Juniper Revealed as the World's Oldest Shrub

A weathered, unremarkable knot of twisted wood, wedged among rocks on the Finnish tundra, has proved to be far more extraordinary than it first appears.

Hidden in the intertwined branches of this long-dead common juniper (Juniperus communis) is an age greater than that recorded for any other shrub. Ring analysis indicates that it began forming rings around 260 CE and eventually withered and died in 1906 CE.

That means the shrub must have germinated earlier still. Researchers calculate that it survived on Earth for 1,647 years before its death.

"Juniper is the most widespread woody species in the world. It is found from sea level to the upper limits of vegetation, from Alaska to Etna, from Japan to Scotland. It is an extremely eclectic species, capable of tolerating scorching temperatures and aridity, such as in sandy dunes, or, conversely, in freezing environments near glaciers," says dendrochronologist Marco Carrer of the University of Padua in Italy.

"Today, this record is joined by that of being the world's oldest shrub."

The world's oldest shrub in the Finnish tundra

Animals and plants are fundamentally different types of organisms, and longevity is among their most intriguing distinctions. Some clonal trees on Earth have endured for tens of thousands of years, while individual trees can reach ages measured in millennia.

These ancient trees warrant protection for several reasons. They retain evidence of historical climate, as well as geological and cosmic events, in the places where they grow. They also form stable hotspots of biodiversity, while groves and forests containing exceptionally old trees make an important contribution to carbon capture and storage.

The juniper shrub at the centre of this finding has been known to scientists for several years. It was found in Utsjoki, Lapland, in 2021, close to the University of Turku's Kevo Subarctic Research Institute.

Scientists initially assessed its age at roughly 1,242 years. However, when they returned to examine it in 2024, they discovered that estimate was wrong: the shrub was considerably older. They also identified four additional juniper shrubs in Utsjoki that were more than 1,000 years old, alongside several others in Sweden.

"The oldest juniper and the oldest woody plant in Finland was a 1,070-year-old specimen found in Lemmenjoki before this discovery," says ecologist Otso Suominen of the Kevo Subarctic Research Institute.

"The age record of Finnish junipers has now been improved by almost 600 years."

How scientists dated the ancient common juniper

To determine the juniper's age, the team counted the rings in its trunk, as woody plants generally add a new layer each year or close to it. They then compared the results with ring growth from other old junipers in the same region to calibrate the species' growth rate.

Junipers are especially susceptible to skipping a year of growth, leaving no ring for that year. By cross-comparing the shrub with other junipers, the researchers could detect those missing periods in the ancient specimen and produce what they consider a more reliable age calculation. Indeed, they think the revised estimate could still be cautious: the shrub's actual age may be between 10 to 200 years greater than the figure they obtained.

Protecting the tundra's ancient junipers

According to the researchers, the tundra probably contains juniper shrubs that are older still, making the case for safeguarding this remarkable biome.

"Current warming at high latitudes, along with consequent natural vegetation dynamics and climate change-driven increases in the intensity and frequency of natural disturbances, may pose even more serious threats," they write in their paper.

"The northward advance of forest vegetation can rapidly outcompete old junipers and alter the natural disturbance regime that commonly shapes tundra assemblages. This emphasizes the need to first recognize and then implement conservation efforts to prevent the loss of this unique component of the tundra biome."

The discovery has been published in Ecology.