Vineyard views

Wines & Vines, Sept, 2003 by Cliff Ohmart

I was inspired to write this column after attending the daylong session entitled "The Science of Sustainable Viticulture" at the June, 2003 annual meeting of the American Society of Enology and Viticulture (ASEV) in Reno. Invariably, when attending events with a sustainable farming theme, I hear one or more presentations that are long on passion but short on data. One of the goals of the ASEV session on sustainability was to try and cut through some of the rhetoric surrounding sustainability by identifying what research has been done and is being done on specific sustainable practices for winemakers and winegrape growers, and to hear from practitioners what sustainable practices are being implemented in the vineyard and winery.

It was clear that a lot of research is going on in the field of sustainability and it was also clear that we have a long way to go in terms of developing science-based sustainable winegrowing practices. There are many reasons why we aren't further along in terms of science-based sustainable viticulture, but it often seems to come down to time, money and a shortage of each.

While contemplating the presentations from the ASEV event, it struck me that great wines have been made using all types of farming methods, whether organic, sustainable, biodynamic or conventional.

This does not stop some practitioners in each camp from talking as if they have all the answers, having found the secret to fine winemaking. Conversely, poor quality wines are produced using each of these farming methods, too. So what does this mean? For one thing, no single approach to farming has been shown to provide "the" answer to growing quality winegrapes and making quality wine. Moreover, since one can arrive at a high quality wine from many different directions, it also means that there is a lot more to learn about growing quality winegrapes and making quality wine before anyone can state he has found the ultimate formula.

Rather than first focusing on what we don't know about growing quality winegrapes, and the variability that we can't explain, let's look for common threads that run through the various farming approaches (i.e. conventional, sustainable, organic, biodynamic) when it comes to successfully producing high quality wines. One common thread is vine balance. Even though we might not all agree on the same crop-to-pruning ratio, number of vines per acre, number of buds per cordon, and so forth, most viticulturists agree that quality winegrapes are produced from a balanced vine: one with the right amount of fruit produced per unit of canopy.

How does one achieve good vine balance? By recognizing that vine balance is affected by many things, such as soil type, soil quality, rootstock, clone, trellis system, irrigation practices, shoot positioning, buds per spur, spurs per foot of cordon-much of which is addressed during vineyard establishment and early vine training. Once the vineyard is established, then close attention must be paid to the vines and the canopy manipulated if proper balance has not been achieved. Fine wines are produced when growers pay very close attention to their vines, regardless of whether the farming techniques are conventional, organic, biodynamic or sustainable, giving credence to the expression "the best thing you can put on your vineyard is your own shadow."

Now let's focus for a moment on what we don't know regarding the growing of quality winegrapes and making fine wines and what we can do about that. One way is for winegrape growers to become better record keepers and to be more quantitative in their measurements.

By record keeping I do not mean pesticide use, payroll, equipment, and other basic financial accounting. Most growers are pretty good at keeping track of these aspects of farming. I am referring to the "accounting" of the cultural aspects of farming winegrapes, like shoot thinning, shoot positioning, petiole samples, fertilizing, pest monitoring, neutron probe readings, weather data and pressure bomb readings.

Why is good quantitative record keeping so important? Because good records tell you very specifically what you have done in the past and, with careful analyses, they can be used to direct future practices. For example, vine balance is affected by many variables and it is only through careful measurement of these variables and analyses of the data that patterns will emerge as to which of these have the most influence on the production of quality winegrapes. It is only through good record keeping that we can develop cost/benefit analyses of specific farming practices.

There are several reasons why growers have up until now been deficient in good record keeping of important viticultural practices. First, many farming practices are hard to quantify in an affordable and meaningful way.

Second, the value of good record keeping is not readily apparent in many cases, particularly to a small grower. It is more apparent when comparing one grower's practices with another, which many growers are reluctant to do, or when considering a grower who farms multiple vineyards.