Bordeaux varietals of Petite Verdot and Malbec in 1963. Today, Hunter Valley Cabernet exhibits more the regional traits of a Hunter Shiraz than it does with the varietal expression of Cabernet exhibited in Bordeaux and California. It tends to be very earthy and is usually cross blended with wine from regions outside the Hunter. Maurice O'Shea of Mountain View pioneered planting of Pinot noir which he used to blend with Shiraz. The Pinot noir grown in the warm Region IV climate of the Hunter exhibits very little varietal similarities with the Pinot noirs of Burgundy and Oregon where it tends to produce a low acid, fruity wine. While an obscure grape mostly associated with the fortified wines of Madeira, Verdelho has developed a niche in the Hunter Valley where its thick skin and high acids tolerate the humidity and heat. Semillon Hunter Valley Semillon is widely considered the iconic wine of the region. First planted in the region in 1830, the grape has been produced and variously labelled as Hunter Valley Riesling, Shepherd's Riesling, Hock, Rhine Gold, White Burgundy and Chablis. In its youth it is exhibits austere lemon, grassy notes but with 10 plus years in the bottle it develop into a rich, minerally wine with biscuit notes. The character of the wine changes so much that it often even fools professional tasters of being an oak aged Chardonnay that has gone through malolactic fermentation, this despite the fact that it likely hasn't seen a touch of oak or lactic acid bacteria. In the Upper Hunter there has been some experimentation with oaked aged Semillon but remained more the exception rather than the norm. Described by Oz Clarke as one of the "wine world's enigmas", the grapes unique profile is attributed to the harsh climate and humidity of the Hunter which coax this low acid grape to higher acid levels than it achieves in the cooler climate of Bordeaux. Typical harvest figures for Hunter Valley Semillon are between 6.8 and 7.4 g/L acidity and 2.8-3 pH while in Bordeaux the grape is usually harvested at around 4.8–5.5 g/L and 3.1–3.3 pH. It is the unique climate that shapes the Hunter Valley's distinctive Semillon. While the textbook profile of Semillon is that of a thin skin, neutral grape that is prone to low acids and fatness in the Hunter it matures over decades into a honeyed wine with toasty biscuit