Curetage (also referred to as curettage) is the name for a special sort of vine surgery that was invented in the Centre Loire of France as a way of dealing with the trunk disease Esca, which has been a big problem in the region. It involves identifying a vine with symptoms (the distinctive tiger stripes on the leaves) which, if left untreated will die. François Dal, a researcher at SICAVAC, the research body funded by the Centre Loire region, read about this technique which had been practised a long time ago, and tried implementing it with a hammer and chisel. It worked, but he could only do three or four vines a day.
Joël Cirotte, a grower in Sancerre, decided to try it with a chainsaw. This worked, but because it was a big chainsaw it was hazardous. So François managed to get a small electric chainsaw, making the process more precise and accurate. It’s like dentistry: you try to remove infected wood (amadou, which is yellow), leaving just healthy wood. If you get rid of it all, the vine recovers. Here François demonstrates the technique (although normally this would be done during June or July). Five years after treatment, 75% of these vines survive, and he thinks that 70% of the growers in the region are now using this technique to save old vines.