Our Vineyard Soils
(The following is taken from an article written in the Dehlinger July 2011 newsletter)
A vineyard-driven wine is made unique by its soil. The site that our family has been privileged to own and operate since 1973 has a distinguished history that goes back about 5 million years. At that time our land, now 13 miles from the Pacific Ocean, was right at the water's edge. Over an extended period a semi-circular ocean bay about 15 miles north to south and perhaps 8 miles east to west was slowly filled with fine sandy and silty sediments that had eroded from nearby older volcanic rock. Ultimately a layer hundreds of feet in depth was deposited. Salt water clams were common and left shell bearing lenses five to twenty feet thick.
Perhaps a million years later along the eastern rim of this bay a related but less extensive deposit was made under fresh water conditions in a strip ten miles north to south, and less than a mile wide. This strip, not subject to the washing of the tides, contained more gravel and a reddish clay. Our property, with 45 plantable vineyard acres, is at the junction of these two deposits and at the extreme northern reach of the second one. Later still, during the Ice Age, the coastal hills were pushed up to our west to a height of 500 to 1200 feet, creating a mild barrier from the ocean, giving us an ideal summer climate - an undulating tension between influences of the cold Pacific and the warm California interior - that winegrapes love.
The larger deposit referred to above has weathered into the Goldridge Fine Sandy Loam soil. Its topsoil is typically gray to brownish gray and about two feet deep with a composition of 70% fine sand, 20% silt, and 10% clay. Its subsoil is typically a yellowish clay loam with an additional three to four feet of depth and a composition of 55% fine sand, 20% silt, and 25% clay. When European immigrants first began agricultural pursuits in this area they found the Goldridge soil to be ideally suited for apples, cherries, and berries. It yielded good crops of high quality and well sized produce without any irrigation, as the substantial depth and the silt and clay fractions in the subsoil could bank enough water to sustain these plants through the generally rain free six month growing season.
The smaller reddish deposit has evolved into the Altamont Gravelly Fine Sandy Loam. Its topsoil is a brown to grayish brown layer only one foot thick with a composition of 5% gravel and coarse sand, 60% fine sand, 22% silt and 13% clay. The associated dull red to brown subsoil is an additional two to three feet thick with a make up of 50% fine sand, 20% silt, and 30% clay. Its total water holding capacity is less than the Goldridge but the higher clay content is conducive to a slow extraction of water over a long period of dry summer growth. The early farmers considered the Altamont less valuable than the Goldridge because the tonnage yields were less. It was planted mainly to apples and wine grapes, the latter crop being favored by the higher aspect of the soil, meaning less likelihood of damaging spring frosts. By the 1920s it had been learned that the Altamont soil would ripen its crops up to a week earlier than the Goldridge, which was a distinct advantage in fresh produce marketing as the very first ripe fruits of summer used to command significantly higher prices.
Our breakdown between the two soils is about 15 acres of Goldridge, 25 acres of Altamont, and 5 that are a hybrid, generally with a Goldridge topsoil and an Altamont subsoil. What we have learned over thirty five years of winegrowing and winemaking on this property is that both soils can produce excellent, unique and distinctive wines which reflect the way that the soil supports plant growth and fruit development. Wines from the Goldridge soils tend to be fruit forward and aromatic, and supple on the palate (especially in the case of Pinot noir). The Altamont soil wines are often more brooding, denser, thick and firm. Since the mid-1990s we have been making Pinot noir and Syrah bottlings from the property with the designation "Goldridge" on the bottle. This means that the wine comes from the Goldridge soil areas of the vineyard. Our bottlings simply designated "Estate Bottled" have been more from the Altamont soil areas but are created vintage by vintage to stay in character.
It would be as wrong to say one wine is better than the other as to state a preference for one of your children over another. We have charged a slight premium for the "Estate" over the "Goldridge " because the latter bears slightly larger crops and is faster to develop and show itself, often being bottled a month or two earlier, and released six months ahead. About a quarter of our Altamont soil acreage, the part occupying the hilltops and ridgetops, has a very thin topsoil and in these areas the grapes grow almost directly in the subsoil and struggle more. Yields average well under two tons per acre and the grapes are small and especially concentrated. These are the spots with special designations such as "Octagon" and "High Plains" that we have bottled in particularly good years when volume has been sufficient. Starting with the 2009 vintage, we have "Altamont" designations on some wines where that is appropriate to match our "Goldridge" designations.