Rootstocks, grafting and when French wine almost died but was saved by Texas | Britt on Forbes

Share / Like:

Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on email

Share / Like:

Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on email

A successful and adventurous journey across the United States in the midst of the phylloxera crises in the 19th century helped save the French vineyards. Pierre Viala, a French botanist, had been sent to find a solution to the phylloxera crisis. He found it in Texas. Viala brought back home an American vine which seemed to thrive on the same type of calcareous soil found in Champagne and Cognac. He had discovered a rootstock that worked for these regions and many others.

A ship that arrived to the south of France in the 1860 brought with it, among many things, cuttings of vines from America. But it carried more than that, an unknown passenger that were to almost wipe out all of France’s, and Europe’s wine production. It was later to be discovered to be a tiny insect called the vine louse, or Phylloxera vastatrix (more recently, it sometimes goes under the alternative Latin name Daktulosphaira vitifoliae). With good reason “vastatrix” means “devastator” or “destroyer”.

This article was originally published in a shorter version on Forbes.com.

A vine leaf showing signs of a Phylloxera attack
A vine leaf showing signs of a Phylloxera attack, copyright BKWine Photography
A vine suffering from Phylloxera vastatrix
A vine suffering from Phylloxera vastatrix, copyright BKWine Photography

The Phylloxera louse feed on the vine’s roots but since vines and the louse had coexisted for a long time in north America the vine had adapted and could survive the louse. But the European vine, Vitis vinifera, could not. When the louse arrives in a vineyard a vinifiera vine eventually dies. As the vine louse spread across Europe, the vineyards died, one after the other. No one knew of an effective protection.

The solution was eventually found, a simple one: you take the root of an American vine and onto it you graft the European fruit-bearing vine variety, Vitis vinifera. Voilà. It is the upper part of the vine that identify what grape variety it is: cabernet sauvignon, grenache, syrah etc. All “European” vine varieties are V vinifera.

We have read many times that chardonnay thrives in limestone soil and cabernet sauvignon in gravel soil. Less is written about the importance of choosing a suitable rootstock. Today, almost all vines are grafted onto American rootstocks, and it is these that are in contact with the soil and thus with the louse. One should, for instance, consider the pH (“acidity”) of the soil when choosing the rootstock.

A vine leaf of an American Vitis species, with different shape
A vine leaf of an American Vitis species, with different shape, copyright BKWine Photography

Nowadays, there are many American rootstocks to choose from, but in the beginning, there was only one, Vitis riparia. (Riparia means “living on the river bank”.) It had good resistance to the dreaded vine louse, a fact they were happy about at the end of the 19th century when they were desperate for a solution to the phylloxera crisis. The vine louse spread rapidly in France and Europe.

There was a problem though, in France. Vitis riparia does not do well in calcareous soils with high pH (low acidity). That kind of soil is common in French wine regions. It covers half of France and many wine regions. To try and solve the problem they tried Vitis rupestris, another American vine, but it didn’t work well either. (Rupestris is Latin for “living on rocks”.)

In 1887 Pierre Viala was commissioned to go to the United States and look for an American vine that could work well in the alkaline (high pH) soils. Viala was a professor at the agricultural school of Montpellier not far from where the original outbreak of Phylloxera had happened. He was also a botanist and from a family of grape growers.

Vines grafted on rootstocks in small pots
Vines grafted on rootstocks in small pots, copyright BKWine Photography

Viala was sent across the Atlantic on a mission to find a solution and started out on an enterprising journey across the United States, from New York to Virginia and from there to Texas. Here in Texas, with the help of a local botanist specialised in vines called TV Munson, Viala finally found Vitis berlandieri. It was growing and thriving in a soil quite like the limestone soil found in Cognac. A Texan vine were to save the French wine industry.

Even more curious is that it is called Berlandieri after the French naturalist Jean Louis Berlandier who travelled across Texas in the 1820s, well before Texas became part of the United States in 1845.

A grafting bench with rootstock material to the left and the graft punch
A grafting bench with rootstock material to the left and the graft punch, copyright BKWine Photography

European Vitis vines, including all varieties commonly used for wine all over the world:

    • Vitis vinifera

American Vitis vines, rarely used to make wine, the best-known:

    • V rupestris
    • V riparia
    • V berlandieri
    • V labrusca
    • V rotundifolia
    • V aestivalis
    • V mustangensis

Discovering that Vitis berlandieri did well in calcareous soil was a good start. The result was even better though when it was crossed with the white grape chasselas, a Vitis vinifera, part of the European grape vine family. Crossing a V vinifera with a variety that is not vinifera creates a “hybrid”. They gave it the curious and not very attractive name of “41B”. Even today, 140 years later, producers use the 41B rootstock all over France, not least in Champagne and Cognac.

Almost all vines today are grafted onto an American rootstock, all over the world. There are some phylloxera free havens, but they are rare. It is mostly in very sandy soil. Chile has also been spared. The American vine is immune to phylloxera. The European Vitis vinifera family, which the majority of producers use for their wines all over the world, is not. Vitis vinifera is the vine family that includes all well-known grape varieties, cabernet, grenache, chardonnay, riesling etc.

Vines grafted and ready to be shipped to the winery
Vines grafted and ready to be shipped to the winery, copyright BKWine Photography

Most of the rootstocks used today were created and selected soon after the phylloxera crisis at the end of the 19th century. Rootstocks received little interest during the 20th century. In France, five different varieties of rootstocks seem to satisfy the need of most growers even though around 30 are approved.

Many use the 41B but the most common is SO4, a crossing between Vitis berlandieri and Vitis riparia. The other three in common use are 110 Richter, 3309 Couderc, and Ruggeri.

An omega graft on a vine, the rootstock to the left, the grapevine to the right
An omega graft on a vine, the rootstock to the left, the grapevine to the right, copyright BKWine Photography

The most common rootstocks in France:

    • SO4 (V berlandieri x V riparia), also called Selection Oppenheim 4
    • 41B (V berlandieri x V vinifera), 41 B Millardet et de Grasset / 41 B MGt
    • 110 Richter (V. berlandieri x V. rupestris)
    • 3309 Couderc ( riparia x V. rupestris), 3309C
    • 140 Ruggeri (V. berlandieri x V. rupestris), 140R

However, with the climate change challenge, the wine industry has realized that it needs a new generation of rootstocks.

Research is focused on obtaining rootstocks with resistance to water stress, as more and more wine regions suffer yearly droughts, and resistance to viruses and other diseases.

The graft of a vine and rootstock, covered in red wax
The graft of a vine and rootstock, covered in red wax, copyright BKWine Photography

But also important is avoiding iron deficiency chlorosis, which could happen in chalky soils (the reason for Pierre Viala’s US adventure), and facilitating the vine’s potassium and magnesium uptake. Experiments involve various crossings of Vitis riparia, cordifolia, rupestris, berlandieri and vinifera.

Even in areas where there is no Phylloxera, e.g. in Chile, some wineries prefer to plant grafted vines. It gives them an additional tool to adapt the planted vine to its environment. Plus it is a protection if the louse would ever arrive.

Maybe it’s time to save a thought for the roots? They actually do quite a lot of the hard work.

This article was originally published in a shorter version on Forbes.com.

Chose your language. Read the article in:

Author:

Author:

Share this post:

Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on tumblr
Share on email

Leave a Reply

Your email address will not be published. Required fields are marked *

  Subscribe to comments:

Notify me of followup comments via e-mail. You can also subscribe without commenting.

SUBSCRIBE TO OUR NEWSLETTER!

25,000 subscribers get wine news every month. You too?