Let’s be honest, sometimes wine speak is ridiculous. We talk about flavors like a “sunset on your lovers brow” or how a wine has “nice legs.” Such talk can be fun and, for some, is part of the attraction to wine. I also like to dabble in such speak once in a while. There is, after all, a certain amount of art in winemaking.
However, there is also quite a bit of science. And it too is as fascinating as the legs on any red Bordeaux!
So, I am starting this new series where I breakdown some aspect of wine grape growing or wine making or maybe some other part of the process of getting wine into your glass. I am going to call it the “Ferocious Focus” series because both those words start with the letter “f” and the series will ferociously focus on one topic in each post. Hopefully you find it interesting.
Let’s start with rootstocks…
Most vines (around 85%) today are not grown on their own roots. When I first learned this, it blew my mind. We are drinking wine made from Frankenstein.
The cause dates back to the 1860s when vines in Languedoc in Southern France started to die for no apparent reason. The French government appointed a botanist, Professor Planchon, to investigate. Professor Planchon discovered that the vines’ roots were being destroyed by a small yellow insect which he named phylloxera vastatrix, the destroyer. Turns out that the designation is scientifically inaccurate but it is still a great name.
Researchers and grape growers put forward many solutions. Some were bizarre, such as burying live toads, which would eat the insects, in vineyards. Some were successful, but not practical, such as flooding vineyards for several weeks to drown the insects or planting vines on sandy soil. Eventually, some researchers determined that the insect had come from the United States and that American vine species were resistant to it. As a result, in 1869, Gaston Bazille suggested grafting European varieties onto the rootstocks of American varieties.
Grafting works because plants do not have an immune system that would cause the plants to reject each other. Plants also have a wound-healing response that allows the scion and stock to join together. Most importantly for the European grape growers who adopted grafting, there is no scientific evidence that grafted vines produce grapes which are inferior to those produced by the same variety grown on its own roots.
Today, there are few areas not affected by phylloxera and where vines are grown on their own rootstocks. Those places are:
- Parts of Southern Australia (strictly quarantined to prevent the introduction of phylloxera)
- Slate soil vineyards in Mosel, Germany
- Quinta do Novato winery’s Nacional vineyard (although surrounding vineyards are infected!)
Think about that the next time you contemplate your glass of wine!