Contemplating Rock Bottom with Winemaker John Faulkner
Netanya and I dug a giant soil pit at Seven Springs back in August. She's the vineyard manager, and I'm the winemaker, and though we both claim to be pretty good on backhoes and excavators, we turned the task over to our friend who's a heavy equipment operator by trade; which is to say, we directed the digging of a giant soil pit. Kyle did the actual digging.
It took him a full day to do it. (See the picture for what a properly dug hole looks like). He sloped the wall of the pit ever so slightly backward–back towards an angle of repose, which is where friction and gravity balance each other out–but not so sloped backward that we lost the dramatic effect of a sheer face.
Dramatic it is! Hundreds (thousands? hundreds of thousands?) of years' worth of deposition and weathering brought to the light of day: and it's but one glimpse of countless unglimpsed such soil profiles in the vineyard.
The wine trade loves to invoke, by describing this or that soil as particularly “ancient,” reverence for the faith of terroir. We stagger our minds with numbers and epochs the better to suspend disbelief. (“Our soil is 70 million years old! A Late Cretaceous metamorphic!” we might say.)
But I think we make terroir harder to interpret by talking this way. The soils of Seven Springs derive from basalt, which is a volcanic rock. (The volcano is long gone. It was somewhere in present-day Idaho, anyways!)
Rock has turned to soil by forming factors, such as wind and rain, cycles of freeze and thaw, by the slow and steady fracturing by plant roots and other organisms... in other words, they've eroded (weathered). And the more they weather, the more they alter. My mentor in the world of terroir, Pedro Parra, talks incessantly about the state of alteration of rock. Alteration means chemical weathering, not just physically eroding. It means the transmutation of one mineral into another. Jurassic plants and animals turn to coal. Coal turns to diamond. The more the transmutation, the less useful it is to refer to these latter forms by their original ones. These changes take place by soil forming factors over time.
So, the stronger the forming factors, the less time is needed to make soil. The weaker the forming factors, the more time is needed.
The Willamette Valley has a lot of these forming factors. It's no secret that it rains half the year. Less known is that basalt is among the most chemically weatherable of rocks. The Willamette Valley grows soil rapidly, as a farmer friend tells me, not to mention everything that grows in soil. To call the place a volcanic terroir is true only so far as it goes. Often the rock is gone.
The trick, in treasure hunting mother rock terroir —in our case, volcanic terroir, is not to find soil, nor is it to find hard rock. Everything grows in soil; nothing grows in rock. The trick is to find soft, weathering rocks.
Rock nerds describe them as alterite. They are the threshold where rock is turning to soil–by definition, the youngest possible soil, the least chemically altered. Where vine roots touch this pay dirt, there's the chance to experience whatever's meant by volcanic terroir. Our soil pit reveals it: rock so weathered it falls apart as you try to pluck it out of the wall. The vine roots break through it easily. There it is: diamond, but in the rough.
In the springtime, it'll be framed with wildflowers. I plan to have a picnic lunch in the soil pit, and drink some wine, and contemplate. Come join me!
- John Faulkner