blended with Sauvignon blanc and Muscadelle. When dry, it is referred to as Bordeaux blanc and is permitted to be made in the appellations of Pessac-Léognan, Graves, Entre-Deux-Mers and other less-renowned regions. In this form, Sémillon is generally a minor constituent in the blend. However, when used to make the sweet white wines of Bordeaux (such as those from Sauternes, Barsac and Cérons) it is often the dominant variety. In such wines the vine is exposed to the "noble rot" of Botrytis cinerea which consumes the water content of the fruit, concentrating the sugar present in its pulp. When attacked by Botrytis cinerea, the grapes shrivel and the acid and sugar levels are intensified. Due to the declining popularity of the grape variety, fewer clones are cultivated in nurseries causing producers to project a future shortage of quality wine. In 2008, 17 Bordeaux wine producers, including Château d'Yquem, Château Olivier, Château Suduiraut and Château La Tour Blanche, formed an association to grow their own clones. Australia Sémillon is widely grown in Australia, particularly in the Hunter Valley north of Sydney, where for a long time it was known as "Hunter River Riesling". Four styles of Sémillon-based wines are made there: a commercial style, often blended with Chardonnay or Sauvignon blanc; a sweet style, after that of Sauternes; a complex, minerally, early picked style which has great longevity; and an equally high quality dry style, which can be released soon after vintage as a vat- or bottle-aged example. The latter two styles were pioneered by Lindemans, Tulloch, McWilliam's Elizabeth, Drayton's and Tyrrell's, and are considered unique to Australia. Most examples of these bottle-aged Hunter Semillons exhibit a buttercup-yellow colour, burnt toast or honey characteristics on the nose and excellent complex flavours on the palate, with a long finish and soft acid. Young Hunter Valley semillon is almost always a dry wine, usually exhibiting citrus flavours of lemon, lime or green apple. Cooler-year Hunter Semillons seem to be the most highly sought after, with some of the 1974 and 1977 vintages still drinking well. The newer, fruit-accentuated styles are championed by the likes of Iain Riggs at Brokenwood Wines and The Rothbury Estate. Sémillon is also finding favour with Australian producers outside the Hunter Valley in the Barossa Valley and Margaret River regions. The Adelaide Hills is becoming a flourishing region for Semillon, with the cooler climate producing some wines of great