The biggest difference between Burgundy and Bordeaux is perhaps on the ground, rather than in the bottle. In Bordeaux the norm is for a chateau or chaise to sit in the middle of an estate and to have one owner. I don't mean necessarily one person - it could be a company or a partnership - but the ownership tends to be invested in a single entity.

In Burgundy it's different. Here famous names like Clos de Vougeot have many owners. In this case the total area of fifty hectares is divided among more than eighty registered owners. Some of these have parcels of reasonable size and homogeneity, others have as little as half a row of vines. Naturally this causes some absurdities: there are owners here who choose to grow their grapes 'biodynamically' and who don't spray, but whose immediate neighbours (some two yards away) are spraying away quite happily and probably on windy days as well.

Just to give some sort of perspective to this the slopes to the north of the town of Chablis are divided into the seven grands crus. When you look up from the town they look like no more than seven big fields, all around 10 or 12 hectares in size except for the 26 hectare 'Les Clos'. As is normal in Burgundy each of these seven fields has multiple ownership. I was curious to know how differing wines could be from adjacent properties; certainly looking at the map you'd assume the demarcation lines are simply the old field patterns, but up on the slopes you can see that the divisions are made on topographical grounds. Where the rolling slopes change in orientation to the sun, where the slope suddenly steepens or evens out, where the soil types change - these are the underlying principles of where the one appellation ends and another begins.

As it happens William Fevre own a parcel of 'Les Preuses' which directly abuts upon another of their parcels in 'Les Bougros', separated only by a road. Their chief wine-maker Didier Seguier poured me a glass of each of these and said ''Les Bougros' is on much steeper ground than 'Les Preuses'; there's less soil so the vines root less deeply and produce less fruit, but make a powerful wine. 'Les Preuses' is on dense clay over limestone, making a wine that ages well.' Like Saint Thomas I needed persuading, but as soon as I sipped the wines I could see he was right. There really are differences and just a few yards is enough to cause them.

Wine of the Week

Sauvignon de Saint-Bris 2001, William Fevre

Before we began our tasting of the prestigious Grands Crus, we tried this wine. Later, after the tasting, we tried it again and it was still good. Simple, crisp, clean and light, it held up well against some heavyweight competition, surprising a few of us. If you're tiring of New World Sauvignons you could give the old country a go with this one.

Available in selected independent off-licenses, RRP €12.50