It's not everyday that someone hand delivers a fossilised 2,000 year old vine plant to my front door, but last week I found myself sitting at my kitchen table with viticulture and agronomy consultant Tamara McIntosh, a Roman vine laid carefully out in front of us.
A photo of the 2,000 year old grapevine. Image credit: Jane Anson
Not that you’d have looked twice at it unless you’d been told what it was. It – or strictly speaking they, because it had been split into two smaller pieces – looked like a shriveled wreck of discarded driftwood, blackened with age and neglect.
But, this was one of the few Roman vines still in existence, retrieved from the Musee d’Aquitaine in Bordeaux – and before that from the Saint-Christoly archeological dig in 1982, near the site of today’s Place Gambetta. It was originally preserved by anoxic waterlogging, probably by an underground water system such as a river or its nearby marshland.
It had taken McIntosh five years of determination and gentle persuasion to get to this point, and my kitchen was just one very small stop on its schedule. The vine was on its way to the Cantu lab at UC Davis in California via Dr Nima Saedlou, an expert in ancient wood – yes, such a thing exists, under the official term xylology – in Saintes. Saedlou was to confirm that it is indeed a grape vine, and Cantu to study its genetic makeup, to better understand how it lived and what it can teach us about modern day vines. And if, like me, you’re worried about cross-contamination, it had already been stabilised for the museum around 30 years ago by a process of gamma radiation in Grenobles.
The vine itself almost certainly dates from Emperor Tiberius’ reign over Bordeaux, around 60AD. These were the very earliest years of the city as a Roman settlement, pre-dating the Roman amphitheatre that once was able to hold over 17,000 spectators and is the most famous relic of the occupation today – and whose ruins by coincidence stand a few minutes walk from my house.
An ancestor of Cabernet?
The hope, it seems clear, is that this is a specimen of a biturica vine – long believed to be an ancestor of today’s Cabernet varieties. A Roman text on viticulture, the third volume of the Roman Empire’s go-to agricultural expert Lucius Columella’s book, De Re Rustica, mentions Roman winemaking in France (or Gaul); and specifically the biturica vine which most believe was the first to come to Bordeaux via their Spanish trade routes. Columella was writing around 40-70AD, so right within the time frame that this vine supposedly dates from, and says of the biturica vine, ‘their wine stands long keeping and attains some degree of excellence with age’.
‘The big question is whether there is any DNA left in here to isolate and sequence,’ says McIntosh. ‘The preservation techniques used in the 1980s involved radiation, and we now know that can be highly damaging, although it was standard practice at the time. Any DNA analysis is delicate – you have to grind down the object being studied and essentially destroy it in order to understand it. It’s a long shot, and clearly there is a highly limited pool of ancient DNA out there, which is why several universities are trying to build up a genetic library.’
McIntosh has a masters in viticulture and agronomy from UC Davis and now works as a consultant in biodiversity and organic viticulture for estates including Chateaux du Tertre in Margaux, but this is a personal project without the benefit of official backing or funding.
Currently, there are pockets of similar research happening all over the world, but to date no coordination between them, and highly limited funding. The idea of even being able to study ancient DNA (aDNA) only dates back to the 1980s, with studies of an extinct but mummified species of zebra held in museums in South Africa. More recently, charred and fossilised grape seeds were found in early 2015 at the Halutza excavation site in southern Israel, that are thought to be over 1500 years old and used to produce the Negev, one of the most renowned wines of the Byzantine Empire. The hope with the Negev seeds is to eventually be able to recreate the ancient wine that was once famous throughout Egypt, Greece, Spain and Italy.
Encouraging biodiversity
The aims here may be more modest, but are no less important. ‘We hope to better understand what the Romans planted, and see if their methods can be useful for modern breeding,’ says McIntosh. ‘Essentially we are looking to understand crop domestication, plant parentage, disease states and environmental factors that can affect vineyards today. I see the study of ancient vines as part of encouraging biodiversity – to improve a breeding line and strengthen a genetic pool you must fall back to wild specimens which are the most genetically rich. These ancient vines may have been closely related to the indigenous grapevines of Europe, many of which are quickly disappearing because modern grapevine clones are too similar, which eventually leads to a drop in quality and less resistance to a variety of diseases. It means that time pressure on this research is huge.’
She added, ‘Once I heard about the existence of this vine when I moved to Bordeaux in 2009, it offered a fascinating extension of my work. The Musee d’Aquitaine had it on display and was reluctant to release any of it at first, but has become very supportive. I sent Dr Cantu a French medieval grapevine fossil to study in 2014 but only bacterial DNA was found at the time – something that is inherent to all fossils. This time around, we will have to wait for a few months before the analysis is completed. It is de-prioritised because of funding so goes into the queue, but the possibility of uncovering something useable makes it worth the wait.
‘These are ancient vines with a direct potential to improve today’s vineyard – and I love the idea that through them we are touching time.’
Written by Jane Anson
