Today is important for the Chevaliers du Tastevin. They are an organisation of Burgundy wine growers, shippers and dilettantes of the world of wine; they hold frequent soirees for which they bedeck themselves with black hats and red robes, and the piece de resistance of their haute chic is a silver tastevin, a little receptacle for tasting wine which is suspended from the neck with orange ribbons.
The significance to them, and indeed to the world in general, of the third Thursday in November is that it is the day each year on which the Beaujolais Nouveau is released to the eagerly waiting connoisseurs.
Should you wish, for some reason, to send a shiver down the collective spine of the body corporate of the chevaliers, all you have to do is whisper the dreaded word phylloxera within their hearing. Phylloxera vastatrix is a parasite that lives on grape-vines - a tiny oval creature a fraction of an inch long that, vampire-like, extracts the goodness from the roots.
An infested plant will gradually cease to thrive, the leaves become fewer and discoloured, the fruit is shrivelled, and ultimately death ensues.
Phylloxera came originally from North America, and was introduced to France in 1869. As it became established during the 1880s and 1890s it caused wholesale devastation in the European vineyards. The cure was simple - albeit drastic and expensive: the vines were all replaced.
It was discovered that wild North American vines were resistant to phylloxera; the best European scions were grafted to imported roots, and the result was a resistant hybrid which bore grapes of vintage quality.
In recent times, however, phylloxera began to reappear in parts of California, but the vignerons nowadays are better armed. When a plant is attacked it takes about two years before the signs of sickness - like yellowing leaves or falling fruit production - can be seen above the ground.
But the key to cost-effective control of infestation lies in early detection of the parasite, and satellites similar to those used by meteorologists are being employed to give this early warning.
It has been found that the temperature of a sick plant differs slightly at any given time from that of a normal healthy one. The difference between healthy and infested zones can be detected from the infra-red images provided by low-orbiting satellites of the LANDSAT series, long before any signs of infestation are detectable to the human eye.
With this early warning system, the outbreak can be controlled by removing a relatively small number of plants, and so the financial impact is reduced.