AMERICAN VITICULTURAL AREA (AVA) ~ a specific grape growing area delineated by the US federal government’s attempt to codify geographic names on wine labels. This scheme was begun under BATF (Bureau of Alcohol, Tobacco, and Firearms), a division of the Treasury Dept with antecedents in the era of moonshiners and Eliot Ness. After 9/11, BATF and their armed agents moved into Homeland Security, and wine labels moved over to TTP (Trade Policy & Programs), a division of the State Dept.

It is probably a mistake to draw comparisons too closely between the AVA system and France’s appellation contrôlée or any other European system. They all have foibles, particularly in the area of enforcement. One comparison is apt, however. Wineries and growers impacted by any of these systems get mighty exercised when the rules are being decided. In France legislators have been shot. It was in Sauternes nearly a hundred years ago that a lawyer said about appellation contrôlée regulations, “Bad laws make bad citizens.”

Since 1978 the US government has allowed either approved AVAs or three descending-sized geopolitical units (the whole country, a state, a county) to be shown as appellations of origin on US wine labels. No other general place names are permitted. The only other place names that are allowed at all are specific vineyard names. The phrase ‘American’ on a label implies the grapes came from more than one state. The name of a state (e.g. California) would imply the grapes came from more than one county within that state. By way of elaboration, there are 59 counties in CA and 48 of them grow grapes. Counties are the smallest geopolitical unit which can be used as an appellation. Cities (i.e. municipalities) can not be used as place names on wine labels. Grapes grown within a city’s boundaries should use the county name instead.

ATF approved 107 AVAs throughout the US in the first seven years of the program, but slowed down after that. In the next quarter century there were only 87 more AVAs approved. As of 2012, of the 194 approved AVAs in the US, 101 are in California. See Wine Institute for names, dates, and sizes.

Anyone may petition for establishment of an AVA. Their application must include, among other things: (1) evidence the proposed name is recognized as referring to the area specified; (2) evidence relating to climate, soil, elevation and physical characteristics which distinguish the viticultural features of the proposed AVA from surrounding areas; and (3) specific boundaries based on features which can be found on US Geological Survey maps. ATF appends the following caveat to all approved AVA applications: “ATF does not wish to give the impression by approving a viticultural area that it is approving or endorsing the quality of the wine from this area.”

It is an on-going criticism that the current AVA system is being constructed piecemeal without any comprehensive overview nor long-term plan. That is one of the primary reasons Australian James Halliday cited the system’s “sheer irrationalities” in his 1993 book Wine Atlas of California, and why American Bob Thompson called the system “mildly comic” in his Atlas of the same year.

There are five general drawbacks to the current AVA system:

(1) Inconsequential AVAs. Examples in CA include Willow Creek AVA in Trinity County (where fishermen outnumber grape vines by a factor way north of ten), Cole Ranch and Benmore Valley AVAs in Mendocino County, Hames Valley in Monterey County, and Lime Kiln Valley AVA in San Benito County. These places contain no wineries and very few grapes. Such vines as do exist there are owned by one grower and sold to one winery which does not use the AVA name on its label.

(2) Official boundary descriptions. Sometimes AVA boundaries make viticultural sense, as when topographic features such as mountain tops, rivers, and elevation contour lines are used. Understandably, and useful from a consumer education standpoint, sometimes boundaries are drawn using easy to identify cultural features like roads. The problem occurs when an AVA boundary is officially described, as they frequently are, using arcane surveyors’ references to a grid of rectangles artificially laid out on paper. This problem is so pernicious that few attempts have been made in the literature, even on CA wine, to actually draw maps of the existing AVAs. And all of those attempts have come up with slightly different results. Official government descriptions are published in the US Congressional Record as written narratives using a technique called ‘meets and bounds.’ Apparently few of these descriptions have ever been reality checked. One actually reads, “…thence north in a southwesterly direction…”

(3) Meaningless marketing umbrellas. Many AVAs are bigger than they should be for viticultural coherence, simply because once the hearing procedure begins, all neighbors immediately outside the proposed borders petition for inclusion. The Feds then make compromises based on political expediency. Sometimes this problem is severe enough to twist the English language, as in the case of Napa Valley AVA. Most English speakers would assume the phrase Napa Valley, at its most expansive, refers to the Napa River watershed. BATF, nonetheless, approved an AVA named Napa Valley which is so large it might as well be Napa County because it includes all the extremely hot valleys east of Napa which have historically shipped their grapes to Napa wineries.

(4) Omission of some useful descriptive names. Because BATF does not initiate any AVA applications, many geographical references which are commonly used by people in the wine industry are not permitted on labels. Hecker Pass in Santa Clara County, or Ukiah Valley in Mendocino County are two examples. Perhaps the most illustrative one is Central Valley. Although that is where most of the grapes have been grown historically, no one wants to petition for the right to use it on a label because it has come to signify jug wine status.

(5) Overlapping AVAs. One of the most confusing aspects of the US appellation system is failure to do anything about incongruities along the borders of overlapping, contiguous, or neighboring AVAs. Within Napa Valley the vintners themselves are attempting a cohesive, unusually logical program to divide the valley into sub-AVAs. In San Benito County, by contrast, the Mt Harlan AVA overlaps the Lime Kiln AVA on one side, but is separated from the San Benito AVA on another side by 200 ft of elevation contour.

The area around the town of Healdsburg in northern Sonoma County is worse. Alexander Valley AVA, Russian River AVA, and Chalk Hill AVA all overlap in one particular spot of about 200 acres. It so happens this spot is also included in the Sonoma Coast AVA, which Sonoma-Cutrer winery pushed through the bureaucracy, and in the Northern Sonoma AVA which Gallo pushed through because label regulations require a winery and a vineyard to be in the same AVA for the winery to put Estate Bottled on the label. Add the umbrella North Coast AVA, plus the Sonoma County and CA state geopolitical appellations which need no AVA approval, and you have eight different appellations under which these few hundred acres of grapes may go to market. As James Halliday put it, “The intellectual nonsense this makes of the system really needs no elaboration.”


AROMA ~ Technically that portion of a wine’s smell which comes from the fruit itself. Different grape varieties have signature smells. Some, such as Sauvignon Blanc, are much more distinct than others. Some wines display their varietal aroma much more intensely than other wines. White wines are much more dependent upon aroma to deliver pleasure than are red wines. Therefore white wines are generally considered diminished if and when they lose their aromatic properties.

The other side of the wine smell coin is bouquet.

Aroma is made up of lighter molecular weight compounds than bouquet. Aroma escapes out of glasses more quickly than bouquet, hence the practice of chilling white wines, and the standard use of smaller glasses which need to be refreshed (repoured) more frequently


ASPECT ~ The direction a vineyard on a slope faces. As one gets further away from the Equator (higher latitudes), the angle of the sun gets lower and lower to the horizon (southern horizon in the Northern Hemisphere, reverse in the Southern Hemisphere). That means a vineyard in northern Europe (say 45º to 50º north latitude) needs a south-facing aspect to get enough direct rays from the sun to ripen grapes. A northern European vineyard with a north-facing aspect would only get oblique rays, and would be in shade much of the day.

California vineyards (32º to 38º north latitude) have the sun pretty much overhead during Summer, so aspect is not usually crucial to getting grapes ripe. Nonetheless aspect can still be important to wine styles and to which varieties do best in which CA vineyards. Aspect becomes more of a factor in CA when vineyards  have steep gradients in mountain districts like El Dorado County of the Sierra Foothills. Similarly, aspect can be crucial in the coastal mountains of California because of fog cover on the western side.


BARREL AGING ~ Barrels are made by coopers. Barrels contribute two things to wine:

  1. gradual oxidation, which softens the tannins and confers more complex smell characteristics;
  2. extract of tannins and flavors from the wood.

In large measure, extract is a function of how long wine has been in the barrel. It is estimated new barrels give up about 60% of their flavoring potential in the first year of use. Hence second and third year barrels have considerably less flavor influence on wine. Barrels older than three years of use would be considered ‘neutral.’ Winemakers generally like a selection of differently aged barrels so as to modulate flavoring influence to their own purposes. Some barrels can be ‘shaved’ after their third year of use to reveal fresh wood, i.e. a router takes the inner surface of the barrel down about a quarter inch.

Both oxidation and extract are a function of a barrel’s surface area to volume ratio. As the size of the barrel increases, volume goes up as a three-dimensional figure (height x depth x width), while surface area only goes up as a two-dimensional figure (h x w). Therefore a 5-gallon barrel will have the same effect on a wine in six weeks that would take a year in a 52-gallon barrel. And a 500-gallon barrel would be considered effectively neutral storage. Most wineries use 52-gallon barrels called barriques. Some wineries like to have at least some 200-gallon barrels called puncheons.

Are smell and flavor from a barrel due to the forest where the tree grew (e.g. Nevers, Troncais, Vosges, etc), or to who made the barrel (e.g. Seguin-Moreau, Nadale, Taransaud, etc), and how they did so? Most coopers and winemakers agree the more significant factor distinguishing barrels is how the cooper seasons and stores the oak so it dries adequately, and how the barrel is fired. Not the species of the oak, nor where the tree grew. Although those two features do make a difference, as does the tightness of the wood’s grain.

A whiskey barrel, of which 3,000 may be made in a single day at a cooperage in Kentucky, will be made with kiln-dried oak which is sawed into staves. The staves will be formed into barrel shape after being made pliable by steam. Then the inner surface will be ‘charred’ by a gas jet flame. Cost is less than $250 each. By contrast a fine wine barrel made at a traditional French cooperage will be made from staves which are split (not sawn), then air-dried for two or three years. The staves will be made pliable by shaping gradually (45 minutes) over a small fire which slowly ‘toasts’ the inner surface (carmelizing carbohydrates in the wood as you might with a marshmallow over a fire, never letting it ignite). The French cooperage may turn only out 25 barrels in a day, but each one is worth about $1,000.

There is no reason American oak barrels can not be made in the French air-dried, fire-coopered manner, and they are. Similarly there are several French coopers working in California, and several French cooperages operating in Napa Valley.

Other price reduction techniques include:

  • Oak chips ~ If surface area is so important to flavor transfer, why not reduce staves to shavings (greater surface area)? Several versions (chips, wands, domino-sized blocks) of this method are widely practiced on inexpensive wines.
  • Micro-oxygenation ~ Why let coincidental oxygen transfer to the wine in a barrel happen when one could leave the wine in a stainless steel storage tank and bubble precise amounts of oxygen through the tank? Some people do just that.
  • Plastic storage containers that breathe ~ New barrels are such a huge expense, and plastic storage tanks exist which do allow an acceptable OTR (oxygen transfer rate).


BARREL FERMENTATION ~ Winemaking technique usually applied to Chardonnay, resulting in richer, toastier, more vanilla-scented, more complex wines. Along with sur lie aging, one of a package of traditional methods affectionately known as “those filthy French techniques” by radical California winemakers back in the 1970’s when Chardonnay was adolescent on the wine scene.

The extra expense of barrel fermentation derives from vastly increased labor, not from the cost of barrels which would likely be employed for aging the wine anyway. Twelve hundred cases of wine (slightly less than 3,000 gallons) would ferment in one stainless steel tank. Barrel fermentation of the same quantity would involve wrangling (filling, monitoring, emptying, cleaning) some 65-70 individual barrels ~ they can’t be filled all the way up because vigorous initial fermentation will drive foam out of the bung creating a gigantic mess. Barrels weigh more than 70 lbs empty, so it’s not like filling, monitoring, emptying, and cleaning 70 wine glasses. Even with only 43-44 gallons in it, each 52-gallon barrique weighs nearly 450 lbs. One doesn’t throw barrels around absent-mindedly.

The other characteristic of barrel fermentation (in most cases) is lack of temperature control. Fermentation generates energy. Temperatures in the barrels go up over 75ºF, which blows off a significant portion of the aromatic properties (fruitiness) in the wine. Ambient air temperature can mitigate this issue. So putting the barrels into a cold box at 40ºF will keep the fermentations around 60ºF, and retain fruitiness. It’s a wonderful trick. Expensive, but works really well.


BENCH ~ Otherwise known as an alluvial fan, and usually described as piedmont or foothills. It is the strip of land between the mountain and the valley floor where large particles (pebbles, sand) fall out of erosional water flowing off the hillsides toward the river in the center of a valley. (See our Tasting Video called Napa Cab Cross-section).

Because a bench has deep, well-drained soil, vines naturally come to a balance between shoot growth and fruit ripeness. It is a favored location. Grapes grown on a bench usually command a premium price. For this reason it is very difficult to draw legal boundaries defining exactly where a bench begins and ends. In a political process excluded growers become very unhappy.

Some instances do exist where a stream has cut a sheer bank into a bench revealing the underground soil structure and clearly demarking the bench, but these are rare. More frequently the embankment has been graded away by farmers on tractors seeking to create gently sloping land. Boundaries tend to follow roads or other visible surface features, and the description of a bench really has more to do with underground characteristics.


BIODYNAMIC ~ In 1909 German scientists Fritz Haber and Carl Bosch demonstrated their process for combining atmospheric nitrogen with hydrogen to form nutritiously available ammonia, which we know as synthetic fertilizer. It is estimated that somewhere between a third and half of the World’s population alive today would not exist were it not for increased food yields made possible by synthetic fertilizer. Haber got his Nobel Prize in 1918; Bosch got his in 1931.

The biodynamic movement began as a backlash to this industrialization of the family farm. Rudolf Steiner was an Austrian philosopher whose early work attempted to draw a connection between science and spiritualism. Steiner died in 1926. His work after WWI included the philosophical underpinnings for biodynamic agriculture. Today biodynamic viticulture and winemaking are the most restrictive level of certifiable ‘green’ practices. The organization which does all the biodynamic certification is Demeter.

Biodynamic viticulture shares with organic practices an aversion to synthetic fertilizer, pesticides, herbicides, and fungicides. Genetically Modified Organisms (GMOs) will never see the light of day on a biodynamic farm, no matter what issue is being addressed. Enhancing the living components of the soil is a central tenet, and therein lies the argument for greater expression of terroir characteristics in biodynamically grown wines. Some departures from organic practices, such as burying cow horns filled with manure, are ritualistic. The biggest difference is a demand for self-sufficiency on the part of the farm unit. Not only must compost and manure be used in lieu of synthetic fertilizer, but the manure must come from animals on the farm being certified. You can’t buy shit from your neighbor.

Biodynamic winery practices are also strictly prescribed. Procedures such as racking the barrels or bottling the wine need to be accomplished on days dictated by phases of the moon.  There are explanations for these requirements involving the moon’s effect on barometric pressure, but it’s hard not to hear superstition.


BLENDING ~ Also called assemblage in France. Usually conducted in the Spring each year. Blending concepts can be applied to any group of wines, be they from different grapes, or different vineyards, or different barrels, or even to different fermentation lots of the same grape variety from the same vineyard.

By way of illustration, in California it is commonplace to source Cabernet Sauvignon from two or three different vineyard locations, and then sit down in the Spring with your staff and a graduated cylinder to audition which combinations seem most appealing. For instance, is 20% from that vineyard on the hillside, 45% from the vineyard on the bench, and 35% from the valley floor more pleasing than 15% hillside / 60% bench / 25% valley floor? Such an artistic decision is complex enough by itself, especially when made in committee, let alone overlain as they so often are by financial questions. What do you do with the remainders after you’ve chosen the “best” blend? Based on price of grapes, each component has a separate cost, and your Marketing Director may have a target bottle price already in mind. Artistry is nice, but can money ever be completely ignored? Then, of course, there is the added complication, both artistic and financial, of introducing other grape varieties (like Merlot and/or Cabernet Franc in our current example) to the blend.

Different parts of your organization will have different agendas. Let’s say you source a total of 100 tons, (composed of Cab Sauv, Merlot, and Cab Franc) from a total of six vineyard sites. That’s a total between 6,500 and 7,000 cases of wine. Your Sales Director might campaign to see it all blended together in a Meritage wine. One label with reliable volume behind it will make her job that much easier. Your winemaker, on the other hand, might lobby for a couple separate wines:

- 500 cases of reputation-building $125 Cab Sauv made with 75% bench CS / 22% bench ML / 3% CF.

- 1,500 css of a $48 Merlot with 85% ML and 15% CF.

- Then the remainder as 4,750 css of a $24 meritage wine.

Bordeaux provides an instructive look at the way assemblage differs from ‘blending’ in California, and how the concept of terroir influences French attitudes about this whole process. Top French wines would never blend grapes from widely separated locations, but on a single estate they would pay little heed to the distinction between grape varieties (say Cab Sauv vs. Merlot). In California the standard operating procedure is for a winery to plant grape varieties in separate blocks, and to ferment grape varieties separately, after picking individual blocks based on optimal ripeness. A classified-growth Chateau in the Medoc is much more likely to pick Cabernet and Merlot together starting at the top of the hill, and do separate fermentation lots daily as they progress down the slope over about a two- or three-week period at harvest. The Merlot goes into the same fermentation lot as the Cabernet picked that day. Assemblage then consists of evaluating different barrels, i.e. fermentation lots. In a warm vintage, the barrels with a higher percentage of Cabernet Sauvignon are likely to shine, and to be included in Estate’s first-string wine. In a cool, or rainy vintage, barrels with a higher percentage of Merlot show better because Merlot gets riper faster (a kind of crop insurance). Barrels blended together during assemblage are chosen based on perceived quality, and nobody knows exactly what percentage of the different grape varieties may be in each barrel.


BOTRYTIZED (pronounced BAH treh tye zd) ~ When clusters of ripe grapes are subjected to moist, warm, still air, chances are they will become infected with a fungus called Botrytis cinerae. Botrytis is fairly common. If you leave strawberries too long in the refrigerator, and they turn into little grey puff balls, that’s botrytis. In grapes the mycelia of the fungus puncture the skin of the grapes. If the moist, still air is then replaced by dry moving air, water will be evaporated out of the berries. Sugar, acid, and flavor will be concentrated. There will also be the addition of a honey-like flavor.

Botrytis makes many of the world’s most famous dessert wines: Sauternes (Semillon grapes) in Bordeaux, Beerenauslesen (Riesling) in Germany, the Tokaji Aszú wines in Hungary, and several others. In both French and German the names used to identify botrytis translate as noble rot.


BOUQUET ~ By convention, that portion of a wine’s smell that is not fresh fruitiness (that’s called aroma, but rather the smell of things done to the wine (yeast, barrels, gradual oxidation from aging). Bouquet is much more associated with red wines than with whites, primarily because reds are more likely to be aged in barrels. Descriptions of bouquet tend to be less natural (flowers, fruits are more about aroma) and more about wood, or smoke, food, or experiences. Chardonnay (which is aged in barrels) is a white wine exception, dependent upon bouquet from its release.


BRETTANOMYCES ~ Also called Dekkera, especially in France. A yeast common to wineries which will metabolize unfermented sugars, including 5-carbon forms which wine yeast will not touch, and will even ferment acids if sugars are not available. One of the by-products of Brett infection, and the compound labs look for when testing for Brett, is 4-ethylphenol ~ which most people would recognize as the solvent used to make adhesive bandages sticky. Another by-product is 4-ethylguiacol. So Brett can have varied smells depending on concentration and what strain of the yeast was metabolizing what substance in the wine. In low concentrations many people describe the smell as ‘shoe polish.’ In high concentrations ‘horse manure’ would be a more apt description.

Aversion to Brett in wines is a culturally defined phenomenon. British writers often refer to a ‘rustic’ character, or a ‘barnyard’ smell. French writers call it an ‘animal’ smell. Technically trained Americans call it a hygiene problem, because use of SO2 and good winery cleanliness usually solves the problem. New York importers of European wines seem to think it is a regional character, which they love to call a gout de terroir . Low concentrations can, in fact, add complexity to wines (mostly reds), but when Brett dominates the smell of a wine, it is definitely a fault. And it won’t be going away with age or with aeration.


BRIX (pronounced bricks) ~ A measurement of specific gravity (the density of a liquid) which is, for our purposes, very close to percent sugar. It is stated in degrees. So grapes picked at 16ºBrix would be severely under ripe. Grapes harvested at 28ºB would be seriously over ripe.

A refractometer is a field device which allows one to put a drop of juice on an optical screen, and then utilize the refraction of light to give a Brix reading. In the winery larger amounts of juice are used with a floating bulb, called an hydrometer, to give a Brix reading, which allows the winemaker to follow the conversion of sugar by the yeast quickly and easily.

Since sugar is converted to alcohol and carbon dioxide during fermentation, winemakers can predict how much alcohol they will have in a wine based on the Brix at harvest. In that manner there are several alternatives to Brix used in other countries: Baume (pronounced BOW may), for instance, is a commonly used scale in Australia, and one can easily convert back and forth between Baume and Brix with a simple calculation.


BROKER ~ An independent salesman who works on behalf of wineries and/or importers, but does not take ownership of the goods. Brokers usually pay their own expenses, and receive a commission on sales. Brokers are licensed by the state(s) within which they work, but they do not pay excise taxes, as those are the responsibility of the owners of the goods. Brokers can be authorized to deliver goods, and to receive payments, and to do billing on behalf of the owners of the goods. Alternatively those services are frequently performed by a third party independent of the sales service.


CARBONIC MACERATION ~ Or maceration carbonique in French ~ is a technique of fermenting uncrushed grapes in an air-tight container which produces the famous nouveau wines, available for consumption about one month after harvest. Beaujolais Nouveau is a marketing phenomenon which garners much attention when these French wines are flown all over the world for parties on November 20th each year. They are the first wines of the harvest, and it is a celebratory time of year. The style of wine is light, red, and fruity with almost no tannin ~ coincidentally, not a bad match with the traditional Thanksgiving meal in America.

What happens technically is the yeast cells areis driven inside the berries through the pedicel (where berry attaches to stem) by the building pressure of CO2 in the fermentation vessel. Fermentation occurs inside the berry. There is very little tannin extraction from the skins. Berries are crushed and pressed simultaneously at the end of fermentation, which essentially means they are treated like a white wine, albeit after fermentation is complete. Many Pinot Noir producers try to adopt aspects of this technique to achieve brighter, fresher, enhanced fruitiness in their wines.

Nouveau wines can be interesting for a brief period, but they do not mature in bottle. Keeping them even six months is a mistake. And don’t drink too much of them during a Nouveau Festival ~ they have a severe laxative effect.


CLARET ~ (pronounced KLAHR eht, with a hard ‘t’) is what the British called red wines from Bordeaux (which they governed from about 1200 through about 1400). It is an English word, not a French word, and the wines 600 years ago were not what they are today. Cabernet Sauvignon didn’t even exist, in Bordeaux or anywhere else, until the last half of the 1600’s. Claret is a corruption of the French word Clairet, which would refer to lighter-colored, lighter-bodied red wines.


CLONAL SELECTION~ Most grapevines are propagated by cuttings, i.e. a shoot from the plant is cut off, forced to form roots, and thus becomes a new vine which is identical to the one from which the cutting was taken. An alternative is sexual reproduction, wherein pollen from one plant gets into the flower of another plant, and a seed forms. This phenomenon is, of course, pretty common ~ the berries from which wine is made all have seeds in them. It is just unusual for vineyardists to raise vines from seeds, because they don’t know from whence the pollen came. Therefore they don’t know what the resulting vines would be like.

A grapevine hybridist will cross two vines by using a small paint brush to introduce pollen from one vine into the flowers of another. The goal is to acquire desirable characteristics (such as flavor, disease resistance, ripening tendencies) while eliminating unattractive features. Just as if you had five children with the same mate, their genetic complement would be very similar, but each child would be slightly different. The same would be true when the hybridist raises 100 vines from separate seeds in her vine cross experiment. She would need to spend the time to raise the vines to see which ones showed which characteristics. In the parlance of grape vines, each vine raised from a separate seed in the crossing experiment would be a separate clone. In all likelihood the hybridist would select the one clone she liked the best, and then promote its future replication via cuttings.

In this manner, the vines generically called French-American hybrids were produced by crossing the European Vitis vinifera with native American species such as Vitus labrusca and Vitus rotundafloria. The goal was to achieve vines with European flavor (winner) combined with American resistance (winner) to cold or insects or fungal diseases. Most of the vines would have been discarded because they showed American foxey flavor (loser) or vines which died at 10ºF during winter (loser).

Examples of clonal characteristics might be two Pinot Noir vines, one of which showed a cola-type smell while the other showed a more cranberry-like smell. Or one Pinot Noir vine which routinely ripened two weeks ahead of other Pinot Noir vines (valuable in cold climates). A famous comparison in Pinot Noir is the clone with an upright, vigorous growing posture (often called Gamay Beaujolais in CA) versus the more drooping posture of most other PN clones.

Clones are officially sold through licensed nurseries in the US. Those from UC Davis Foundation Plant Services are usually identified with a number preceded by ‘UCD.’ Those from the corollary agency in France (ENTAV = L’Etablissement National Technique pour l’Amélioration de la Viticulture) are usually identified by a number preceded by ‘Dijon.’

[See also Grafts]


CLOSE SPACING~ Viticultural research by the Univ. of California from Prohibition to 1970 was overlain with the goal of increasing productivity.  On the UC Davis campus, for instance, there is a single Muscat vine which covers an entire acre. Even more impressive was a single Mission vine planted in Carpenteria (halfway between Santa Barbara and Los Angeles on the coast) in 1842, which by 1892 was nine feet in circumference, and bore 10 tons of fruit each year on an arbor covering two acres.

In that milieu it was determined roots would eventually expand to fill 100 sq. ft. of top soil space. If the canopy were maximized by trellising techniques, production would be pretty much equal irrespective of how many trunks there were. Given this viticultural mindset, the logical recommendation for decades was to space vines for the convenience of moving mechanical equipment between the trellised vine rows: 8’ between vines in the row x 12’ between rows (410 vines/acre) for most grapes in warm areas; 6’ x 12’ (540 vines/acre) for cool climate areas.

Closer spacing was introduced to the debate in Napa around 1980 by the Rothschild-Mondavi partnership at Opus One. The Rothschild advisors planted a demonstration plot in front of the new winery in Oakvilleusing metre-on-metre spacing. Ten years later the phylloxera epidemic in Napa Valley gave everybody the opportunity to re-examine their vineyard spacing decisions. Close spacing appeals to vineyardists seeking to modulate growth in their canopy. ‘Gorilla vines’ which tumble over into the rows, and which have to be hedged, have long been the norm in California. In productive sites with deep soil and lots of access to water, these CA vines keep growing shoots and leaves even past harvest. The idea behind close spacing is that root competition limits canopy growth. Shoots in a closely spaced VSP canopy grow about 40” above the cordon, then stop growing naturally. The stems of the clusters begin to lignify at the end of the season instead of remaining green with sap flowing in them. Moreover the pips (seeds) begin to turn from green to brown at harvest, signifying larger, less astringent tannins.

Close spacing is more expensive because there may be 1,500 to 3,000 vines per acre, and because specialized equipment will be necessary to work in a more confined space. French tractors ride over vines while straddling the row, rather than between rows. A move to close spacing does not, however, require ripping out an existing vineyard. In an 8’ x 12’ vineyard, for instance, additional rows can be planted down the middle of existing rows, and vines can be planted between each vine within each row. That produces 4’ x 6’ spacing (about 1, 800 vines/acre).

[See also Grafts]


CONTINENTAL CLIMATE~ The difference in Average Daily Temperature from January and ADT from July. The opposite of Continental Climate would be Maritime Climate. Continental implies a big difference ~ on the order of 50ºF ~ between Winter and Summer. It also implies a shorter growing season, with concern about Frost in both Spring and Fall, and perhaps the danger of Winter Kill.

In Spring the danger is an uneven break-up of the cold weather. In other words ten days of warm temperatures in April or May, which causes the vines to start growing, followed by a several days of freezing weather, which destroys tender new shoots. Frost damage in the Spring seriously reduces one’s crop. There are various forms of frost protection, but they are all expensive, cumbersome to use, and ineffectual in severe conditions. Fall frost knocks all the leaves off the vines, thus signaling an abrupt end to any further ripening for the year.

Vitis vinifera (European) vines won’t survive prolonged temperatures below -5ºF. That’s Winter Kill. Bending vines to the ground, then covering them with earth, is one technique employed in areas with very cold Winters. It’s a lot of work. And it takes time to accomplish. In the Finger Lakes of upstate New York there was an event in 1980 called the Christmas Massacre. Temperatures went from 45ºF on Xmas Eve to -25ºF on Xmas Day. The vines still had sap in them. The tops of the vinifera vines (what most people think of as wine grapes ~ e.g. Chardonnay, Riesling, Pinot Noir, etc) all exploded. Those vines died. With one exception, there is no such thing as a vinifera vineyard older than 1980 in the Finger Lakes. That singular exception was a Chardonnay vineyard on the eastern shore of Seneca Lake. The very cold wind from the northwest that Xmas night was warmed just enough by the water as it crossed the lake to allow some of those vinifera vines to survive.


CORDON ~ The arms (trained branches) of a grape vine which extend horizontally out from the trunk along the trellis wires of the vine row. The cordon is not pruned. Shoots grow out of the cordon each year, and then these are pruned back. One can usually count the number of spurs left on each cordon, and then the average number of buds per spur, to guesstimate the size of the crop the vineyardist is expecting (figure one shoot per bud, and two clusters per shoot).


CORKED ~ A fault which can occur in bottles of wine with natural cork closures. It is caused by a compound called 2, 4, 6-Trichloroanisol (TCA). The indication is a musty smell often described as wet cardboard. It gets into wine from corks which had a small thread of fungus (the mycelium) in them when they were bleached. The range of sensitivity to TCA is fairly broad. Some people merely experience an affected wine as diminished in fruitiness, sort of dampened down. Other people get a full-blown, unpleasant, additional smell. Similarly the concentration of TCA can vary dramatically from one corked wine example to another.

The occurrence of this fault in corks is random, and there is no reason to assume other bottles in the same case will have the same problem. Australasian winemakers claim the problem may be as wide-spread as 5% to 10% of bottles. Hence their universal interest in a move to screw cap closures for most wines. American winemakers feel the incidence is much lower; say 1% or at most 2% of bottles. My personal experience at large wine competitions would tend to support the U.S. winemakers’ position.


CRUSHER – STEMMER ~ When grapes arrive at a winery, the first order of business is usually to remove stems from the clusters, and to split berries so the juice runs out. Home winemakers accomplish this task by rubbing clusters on a horizontal board with holes drilled it. Berries, seeds, and juice fall through the holes, while stems stay on top. Machines operate essentially the same way. First cluster pass between a pair of grooved rollers which break the skins of the berries, and start removing them from the stems. They drop into a cylinder with holes in it. There is an axel inside the cylinder with paddles on it arranged in a helix pattern. As the axel rotates the paddles rub berries off, and stems are expelled out the back end, while juice, seeds, and skins drop through the holes into a trough on the bottom. Crushing and stemming grapes goes very quickly. The bottleneck limiting speed at wineries is the press.

Refinements include an ability to remove the rollers, and to vary the distance from end of paddle to perforated cylinder, thus allowing a larger percentage of berries to pass through the mechanism removed from stems, but uncrushed. Hence the name ‘whole berry fermentation,’ which is thought to increase fruity aromas while decreasing harsh, grippy tannins. Certainly it becomes by degrees a gentler process with less trauma visited upon the stems. When those stems are still green (with sap in them), as is usually the case in California, it can be a considerable advantage not to tear them up ~ thereby introducing bitter flavors to the wine.

See carbonic maceration.


CUSTOM CRUSH ~ Winery services for rent at a facility with excess capacity. Hence the normal connotation is crushing, fermenting, and pressing. But many facilities will help with sourcing grapes, offer winemaker consultation, provide barrel storage, and bottle the wine as well ~ the complete vanity label experience. What custom crush facilities do not do is sell the wine.

Custom crush facilities are very popular in California, especially for growers, who want to have five or ten tons (300 to 600 cases) made for their own label from their own grapes. If they achieve any success in the marketplace, they can consider building their own winery in due course.

Almost by definition, custom crush facilities work to a ‘recipe.’ That means the contractee (or more likely their winemaking consultant) delivers to the facility a ‘work order’ specifying what will be done to the wine. Each step on the work order has a price, and becomes part of the contract. There is very little room for last minute manipulation, such as longer maceration time on the skins. And small, experimental lots (such as one ton of grapes) are virtually unheard of. Even five-ton lots are discouraged at wineries large enough to be doing much custom crush business. Cool fermentations and extended maceration times take up tank space that could be profitably employed with new fermentation lots. Similarly barrel-fermentations of Chardonnay are way too labor intensive for custom crush facilities. Paying extra money is always a possibility, but it is hard for facility managers to be very flexible during the mild hysteria of harvest.


DEGREE DAYS ~A measurement of how much heat a wine producing region gets during the growing season in an average year. Used to compare regions for their suitability to different grape varieties.

Most grape vines begin growing (i.e. sap starts flowing and buds start pushing) when the Average Daily Temperature (add coldest temperature at night to warmest temperature during the day, then divide by two) reaches 50ºF. So, to get Degree Days for a region, one must add up the degrees over 50ºF in the ADT for every day in the growing season, which in the northern hemisphere is 1 April to 31 October. Do not subtract for days ADT is below 50ºF. Example: on 1 April the ADT is 48ºF, on 2 April it is 50ºF, on 3 April it is 52ºF, on 4 April it is 53ºF. That four-day period has given us 5 Fahrenheit Degree Days. Continue every day until 31 October.

Note ~ countries which use the metric system will render Degree Days in Centigrade, which will seem very low to Americans, and which will need to be translated into Fahrenheit for comparison to US regions.



1) < 2,000 º Days ~ northern Salinas Valley ~ Gewürztraminer, Pinot Noir, grapes for sparkling wines ~ Germany, Champagne

2)  2,000 to 2,400 º Days ~ Sonoma’s Santa Rosa Plain ~ Chardonnay, Riesling, Pinot Gris ~ Burgundy, Alsace

3)  2,400 to 2,800 º Days ~ middle of Napa Valley ~ Syrah, Sauv Blanc, Semillon, Merlot ~ Bordeaux, northern Rhône Valley

4)  2,800 to 3,500 º Days ~ Paso Robles ~ Zinfandel, Cabernet Sauvignon, Grenache, Barbera ~ northern Italy, southern Rhône

5) > 3,500 º Days ~ San Joaquin Valley ~ Petite Sirah, table grapes, grapes for port-like wines ~ southern Italy


The system of classifying regions by Degree Days was developed at UC Davis. It was widely used in the ‘60s and ‘70s, but has fallen out of favor more recently. It does make a fairly broad generalization. For instance, try comparing a vineyard in California on the western side of the Coastal Mountains to one on the eastern side. Both will reach a similar high for the day at about 2:00 pm in the afternoon. Therefore they will have roughly comparable Degree Day scores. The western vineyard, however, will be covered in fog until 10 am (and again after 5 pm) many days in the late part of the season. The eastern vineyard will likely not see that fog, and certainly not as frequently. Hence, irrespective of temperature, the eastern vineyard receives a lot more candlepower of sunshine, and ripens the same grapes two or three weeks faster.


DIRECT TO CONSUMER (DTC) SALES ~ Wine sales which disintermediate (i.e. by-pass) the middle men of the Three Tiered Distribution System. A politically controversial matter since the late 1970’s, at least when it involves shipping across state lines, because it is so vigorously opposed by well-connected distributors and their well-funded lobbying groups.

Why distributors care is a legitimate question. Inducing Orrin Hatch (Mormon Senator from Utah) to say DTC sales across state lines suborn the morals of school children is, of course, ludicrous. There were some 7,400 wineries in America in 2011. Fifty of those wineries sold 83.4% of the total wine volume, but only 3% of the total DTC wine value. DTC sales accounted for 8.6% of wine value in the US from mid 2011 to mid 2012. It would seem the controversy is a little bit of a tempest in a teapot.

However, the potential for small wineries to sell expensive bottles DTC across state lines does appear to hold significant downstream benefit. Between August 2011 and July 2012, US wineries making less than 5,000 cases annually (77.7% of total US wineries) sold 23% of the DTC value. Total DTC volume in that period was about 3 million cases at a value of $1.355 million. The average price of a bottle sold DTC was $37, but for wineries making under 1,000 cases per year the average price per bottle sold DTC was $51.


DISTRIBUTOR ~ Also known as a wholesaler. Distributors buy wine from wineries or importers, then resell it to retail stores and restaurants. Traditionally they work on a base 25% gross margin, i.e. buy a bottle for $5.00 and sell it for $6.67 (the retail store asks $10 and the restaurant asks $15 to $20). Distributors have sales forces, and accounting departments to perform billing tasks. They also maintain warehouses to store inventory, and delivery trucks. Distributors hold licenses from the state, and pay excise taxes on their inventory. Distributors set prices to retailers and restaurants. They also negotiate special deals and payment terms.


DIURNAL FLUCTUATION~ Difference between coldest temperature at night and hottest temperature during the day. 10ºF would be a very small diurnal fluctuation, and would imply a maritime climate wherein a large body of water is modulating temperature shifts. 50ºF would be a very large diurnal fluctuation more common to mountains, most famously encountered in the high deserts.

The effect of diurnal fluctuation on grape growing is a matter of some debate. Most vintners whose property experiences high diurnal fluctuation hew to the analysis that high daytime temperatures ripen their grapes reliably, while low nighttime temperatures preserve acid in the berries for good balance. In other words, they think it is magical. Dr. John Gladstones (love that name, ed.), a viticultural researcher at the Univ. of Western Australia, begs to disagree. His studies showed grape vines metabolize most efficiently at 70ºF. As the ambient air temperature rises or decreases above or below that point, the vine slows down its production of the precursors to flavor. Above 90ºF or below 50ºF vine metabolism virtually stops.

Now, it should be pointed out the nearest premium wine producing region to Dr. Gladstones is Margaret River, which sticks out into the Indian Ocean, and is pretty constant at 70ºF night or day, Winter or Summer. Hometown bias not withstanding, I happen to buy Dr. Gladstones’ argument. He is not saying minimal diurnal fluctuation at 70ºF is better or worse in terms of wine quality ~ at least I don’t think he is. He’s saying it produces a different style. My tasting experience is entirely consistent with that position. Wines from California’s Central Coast are grown with minimal diurnal fluctuation. They have a very long hang-time. Stylistically they are round and slurpy in the middle with dense fruit character. A graph of their flavor profile would look like a boa constrictor who swallowed a watermelon. Wines from high elevation in California’s Sierra Foothills have a big diurnal fluctuation. Their season is much shorter, akin to that of northern Europe. A picture of their flavor profile would be more rapier-like, i.e. longer and thinner. One picks one’s own preference. I’ve heard many northern Europeans accuse Central Coast CA wines of being “too simple, all fruit.” Rather, I think, like opining, “Faith Hill is all legs.” At the same time I hear Americans disparage northern European wines (and those from high elevation in the Sierra Foothills) as “hard, too sharp, very austere.” I think they are being overly critical. Instead, I would say, “refreshing, focused, elegant.” Diurnal fluctuation may be at the heart of the matter. Either way, one man’s meat is another man’s poison.


DRY EXTRACT ~ Sum of the non-volatile solids in a wine, i.e. what’s left after the liquids have been evaporated away. In dry wines it is primarily pigments and tannins. It is a good measure of the perceived density or concentration in a wine. Interestingly, high extract is not the same has full-bodied. German Rieslings, for instance, are famously light-bodied and light-colored, but very high in extract.


EL NIÑO ~ Also called the Southern Oscillation, is a weather phenomenon of the central Pacific Ocean whereby warm surface waters near the Equator begin to migrate westward toward the Americas. They bring unusual quantities of warm rain from the south to wine regions of California, and cause tropical species of fish to be caught much further north than usual. The sardine and tuna industries off the coast of Peru are devastated. Meanwhile Indonesia suffers from drought and Australia from fires. The cause of El Niño is not understood. At first glance it does not appear to be regular in its intensity nor its periodicity. Measuring surface temperatures of the ocean does, however, allow the impacts of El Niño to be easily and accurately predicted. The opposite phenomenon ~ drought in California; flooding in Indonesia ~ from warming surface temperatures near the Equator in Asia is called LA NIÑA. Major El Nino years in California have been 1972, 1982-83, 1998, and 2009-10 ~ with 1998 being the strongest on record.


EVENING SUN ~  (cf: Morning sun) Many of California’s wine growing districts are north-south running valleys. As the sunsinks in the west each evening, vineyards on the bench and hillsides of the eastern half of the valley are in line to get direct rays from the sun. By contrast, those vineyards on the bench and hillsides of the western half of the valley are in the shade of the mountains behind which the sun is setting. Both sides get equal hours of direct rays (the Westside vineyards get theirs just after dawn each morning), but the eastside vineyards get theirs when ambient air temperature is high during the late afternoon. That can makes a significant difference. Eastside vineyards usually produce grapes with thicker skins and more pigment. They often have more polyphenols. The red wines can smell more roasted and leathery.


FIELD BLEND ~ European concept brought to California around turn of last century (1900) by Italian immigrants. Different varieties of grapes are chosen, and promiscuously planted throughout a vineyard, to provide a ‘recipe’ for the wine. Not only is there an attempt to get varieties which will compliment each other in the wine, but also varieties which will act as insurance in different vintage conditions. So a couple varieties should ripen early, and a couple should ripen late. That way, in a disastrously cold, under-ripe growing season the early ripening grapes will save the day, and the late ripening varieties can be left in the field.

Zinfandel was a popular variety for these vineyards. So was Petite Sirah (good color). There was a lot of Carignane, and Alicante Bouchet (fruity, and unusual because it has red pulp). Grenache, Syrah, and Mourvèdre (for a long time called Mataro in California) were less prevalent, but frequently found. It was not uncommon to find 20 or 30 varieties in a single vineyard. Since most of these vineyards were managed by a single family for their own consumption (and that of their relatives and friends), they would usually be three to five acres, and located around the owner’s home. Most would be head pruned, in the wagon-wheel style, by the owner.

Today these vineyards are 70-years-old to 120-years-old. They make really good wine. All the grapes are picked at once, and then fermented together ~ as opposed to trying to identify separate varieties and then pick them according to ripeness. Hence the name: field blend.


GOUT de TERROIR ~ A literal translation from French would be taste of the earth. The implication of the phrase, however, is a taste (or smell) which conveys a sense of place, a signature of the location from which the product comes. In wine that means a particular taste (or smell) typical of the vineyard where the grapes were grown. A taste (or smell) which is predictable, and likely to show up vintage after vintage.

Now, let’s consider an instance where some unusual micro-organism has gotten established in a winery. It gives every wine which comes out of that winery a particular smell. May be nice ~ say hot peanut butter. Not exactly a disaster as a back-note in red wine. Or it may be a more controversial funk. Many experienced wine drinkers would call that characteristic a gout de terroir. If the subject were cheese, I’d agree. Hundreds of dramatically different cheeses are produced around France every year from largely the same raw material ~ milk. The difference between all these cheeses is the action of the micro-organisms peculiar to each district. Why isn’t our wine example the same thing?

Well… Number One I think terroir in wine needs to be a function of the vineyard, not the winery. Two, as a Californian I think the wine micro-biology example cited above is an example of a hygiene problem which obscures the natural taste of the wine, and makes everything coming out of that winery taste the same, no matter where the grapes came from. That’s my personal opinion, but the cheese argument does have kind of a persuasive weight.


GRADIENT ~ The slope of a vineyard. It can be very gradual, as in gently rolling hills, or pretty extreme, as in many German vineyards which are draped along the northern bank of rivers. Steep slopes are, of course, very difficult and strenuous to work. Vineyards there are expensive to establish, and they don’t have much top soil (it washes away in the rain). Hence grape tonnage per acre tends to be low. Low productivity and expensive maintenance naturally implies the wines must be costly. However, low tonnage often also leads to small berries with concentrated flavor, which can justify the price. 


GRAFTS~ Grafted grape vines are not the same as hybridized, or sexually crossed, grape vines, although they do achieve some of the same results. A ‘scion’ is grafted onto a rootstock.’ The genes are not melded together, as they would be in a sexually hybridized vine. The characteristics of the ‘scion’ portion remain intact above ground, while those of the rootstock portion remain intact below ground. The graft is where they join. Hence, V. vinifera (the European vine) is commonly grafted onto an American rootstock. The European vine confers the flavor we want, while the native-American vine confers winter hardiness and resistance to Phylloxera (a native American louse which eats the vine roots).

On most woody plants there is an outer layer of protective bark. Then, moving inward, there is a layer of living tissue called phloem through which capillary action moves sugar and food down from the leaves to the roots and to other parts of the plant. Then there is a layer of rapidly dividing cells called cambium. Next come several layers of living tissue called xylem through which sap moves water and minerals up from the roots to the leaves. Finally comes the heartwood, mainly consisting of xylem layers from previous years which are no longer alive, nor active in this exchange of fluids. [Note: it is by counting these annual ‘rings,’ or previous xylem layers, that one can ascertain the age of the plant.] Successful grafting requires getting the living cambium layer of the ‘bud’ being introduced to match up with the living cambium layer of the receiving plant. Those layers, at most, are only a couple cells thick. The process is not intellectually rigorous, but it does require a certain manual dexterity, and attention to detail. Experience is useful.

One of my favorite wine industry stories involves two physician brothers, one a heart surgeon, the other a cosmetic surgeon, who owned a Santa Barbara vineyard (Carey Vyd). They wanted to convert a block of vines from Chardonnay to Merlot. This technique {called T-budding) involves sawing off the top of the vine, making vertical slits on opposite sides of the trunk up at the sawn top, placing buds of the new vine in each slit, lining up cambium layer contact, and bandaging the wound. The Drs. Carey decided to do it as a competition with their vineyard crew. The surgeons were significantly slower than their Mexican workers. The Carey’s got a 75% ‘take’ (3/4 of the buds they placed grew out as shoots the next Spring). The Mexicans got a 95% take. To their credit the Carey’s were proud of their crew, and talked about the outcome. Of course rhinoplasty does continue to pay somewhat better than T-budding.

Bench grafts are usually done in a nursery prior to planting in a vineyard. Bench grafts are easier than T-budding, and thus cheaper. In a bench graft the stem of the scion and the trunk of the rootstock are selected to be about equal in diameter. That makes alignment of the cambium layers, and bandaging of the joint, simpler. It is also easier to do grafting work seated at a table, than it is to do it with any precision while kneeling in the mud of a rainy vineyard.


GREEN HARVEST ~ Dropping part of the crop on the ground prior to harvest in an attempt to concentrate flavors in the remaining crop. Clearly a smaller crop means less money to the grower. So an agreement to perform green harvest usually involves the winery paying by the acre rather than by the ton.

If clusters (or portions of clusters) are removed from vines prior to veraison, the cells in each berry will simply multiply, enlarging berry size and compensating for the removed crop by raising berry weight and cluster weight. After veraison, berries lose this ability to add additional cells. So dropping clusters on the ground before veraison doesn’t have much effect, either on crop size or on intensity of flavor in the wine. Dropping clusters after veraison means the flavoring materials formed in the last six weeks of ripening will be spread among a smaller crop making for more intense wines.


GSM ~ Red wine blended of Grenache, Syrah, and Mourvèdre grapes. Abbreviation used colloquially in the US and in Australia to approximate the red blend most common in the southern Rhône Valley of France. Not approved for label use in America. In general the Grenache is dominant and provides a berry fruit component. The Syrah provides color, even in small percentages, plus spiciness to the flavor and length to the finish. Mourvèdre (sometimes called Mataro in California, and Monastrell in Spain) supplies weight and mouthfeel.


HANG-TIME ~ How long grapes stay on the vine. Long hang-time is characteristic of cool maritime climates. Because there is virtually no freezing weather throughout Winter, vines start to push buds early ~ by the end of March in California’s Central Coast. That is 6 to 8 weeks ahead of Burgundy,Champagne, and Germany. Cool maritime districts develop more slowly throughout the growing season, and districts at high latitudes catch up because they have longer days until late September. But maritime districts like California’s Central Coast also get an extension at the end of the season. Burgundy,Champagne, and Germany all have a climactic end to their growing seasons, whenever they get a freeze ~ usually around the middle of October. In all likelihood Santa Barbara and Monterey in California would not have even seen a rainstorm by then. Central Coast grapes can stay on the vine into December if necessary in order to achieve full physiological ripeness. In all,Central Coast grapes are on the vine 8 weeks longer than in Napa, and 12 weeks longer than in northern Europe.

The effect on the wine is to imbue it with a lovely roundness on the mid-palate. The wines are very fruity in the nose, and good ones are concentrated with a juicy density in the middle.


HEAD-PRUNED ~ Traditional way of training grapevines in California prior to WWII when the University of California began recommending trellised rows. Hence today head-pruned is almost synonymous with older vines. There are a lot of ancient, head-pruned Zinfandel vines in California originally planted on gently sloping hills by immigrant Italians for their home consumption. Those vineyards are very well-regarded by modern wine connoisseurs.

Head-pruned vines have a knot of dead wood at the crown of the trunk, usually 18” to 3’ off the ground. The vines may be cane-pruned (Gayot) or spur-pruned (Gobelet). Spur-pruning results in a wagon wheel effect which is very visually attractive in Winter when the leaves have fallen, giving the vines a sculptural presence. It is a bit of artistry to prune vines in this manner, and it was usually done by the owner of the property around his own house ~ takes about fifteen years before the vine gets big enough for the work to be apparent. One of the advantages to this style of pruning is that shoots and leaves grow in an umbrella fashion open in the center to allow dappled sunlight onto the clusters. One of the disadvantages is that pickers have to search through the vine to get the clusters at harvest.

An easier alternative is to train the vine with a helix of spurs vertically up a 4.5’ trunk. This technique looks more like a Christmas tree, and is functionally a vertical cordon. This second technique is the one most owners would employ when they hired workers to do the pruning in vineyards away from the home.


IMPORTER ~ Legal entity licensed by the Federal government to bring wine into the country. Importers then sell to distributors in separate states, and pay Federal Excise Taxes. Importers are responsible for getting wines analyzed, and for getting label approvals from the Federal government. In California an importer can also hold a retail license and sell Direct To Consumers.


INTEGRATED PEST MANAGEMENT ~ The ‘green’ practice of identifying (and encouraging) good bugs and animals which will prey upon destructive bugs and animals in the vineyard. Cats in the granary (to catch mice) would be an ancient example. Barn owls to prey upon gophers is a more recent example. The most famous example is a species of wasp that inhabits blackberry bushes, but eats leaf destroying mites in the vineyard. Likewise most people know about lady bugs which eat aphids. Some newer efforts in California involve sowing host plants in the vineyard to attract beneficial insects.

Integrated Pest Management might seem obvious. However it is a considerable departure from spraying pesticides against destructive insects, and in the process wiping out ALL the insects in one’s vineyard.


LATE HARVEST ~ Implies grapes left on the vine beyond normal ripeness, although in the service of dessert wine, rather than in the idiom of ultra-ripe. Late harvest is an imprecise term. Wineries use it in a variety of ways, but they always intend to convey extra effort and extra expense. Sometimes it really just means they ran out of tank space or forgot about the grapes. The term is not covered by government regulation.

Late harvesting raises sugar levels in the grapes. Brix levels of 27º up to even 40º can result. Unfortunately acid levels drop simultaneously. One ends up with cloyingly sweet wines which lack vibrancy. Winemakers can add acid, which helps, but often there is a raisined smell.

Two techniques do a much better job concentrating must (i.e. grape juice for wine prior to fermentation) for dessert wines. One, icewine, has become a staple of the Canadian industry. It involves leaving grapes to freeze on the vine, then pressing them while they are frozen, so that water is removed in the form of ice. Sugar is concentrated (i.e. elevated), but so is acid and flavor. The wines can be magnificent.Canada has more extreme standards than anywhere else in the world (read Germany and Austria). The Canadian grapes can’t be picked at a temperature higher than 17ºF. They have to be pressed at the vineyard (no diddling a batch in the truck). The Canadians are confident they will see those conditions every year if they just wait patiently.

A mechanical knock-off of the icewine technique is called cryo-extraction. Being unregulated, it has a certain cachet in the US. Basically it involves freezing the juice and filtering out the ice. Works pretty well, and is considerably cheaper than Canadian icewine. If you taste the two versions side-by-side, you’ll definitely prefer the true Canadian model. Those grapes have actually frozen, then thawed, then frozen again many times until the 17ºF standard is achieved. The result is an exotic tropicality to the intense fruit of the wine.

The second technique is botrytized grapes.


LEAF-ROLL VIRUS ~ Often called Red Leaf Virus, is actually a suite of at least nine viruses (which researchers have identified so far) which affect grapevines differently depending on species and variety, much like cold and flu viruses affect human beings. The viruses are transmitted very slowly from vine to vine, in all likelihood by a pest called mealy bugs. The symptoms of virus infection are delayed maturity, reduced production, and the characteristic color change of the leaves at the end of the season.

Because of the hit to production, and because virused vines often stop ripening around 16ºBrix (when the leaves turn red, chlorophyll is gone), UC Davis made a decision back in the 1960’s to eradicate virus from vines in California. They originally did that in individual vines by planting cuttings in sand, then heating the sand to 120ºF for about six weeks. Then those ‘heat-treated, virus-free’ vines were propagated by licensed nurseries for sale to vineyardists. UC Davis was very successful. Today 95% of the vines in California are virus-free. At the end of the season the leaves of heat-treated vines merely turn brown and fall off, starting next to the trunk. Whenever you see eye-catching red and orange patches in a vineyard in the Fall, those are virused vines.

The matter is not without some controversy. Certain iconoclast growers and winemakers say, “If most grapes in CA are too ripe, with low acid, why wouldn’t I want a policeman in the vineyard to guarantee low production?” UC Davis-trained viticulturalists respond, “Tuberculosis will make you thin. Does that mean it is a good idea?” Suffice it to say the UC Davis position is by far the more widely held. I personally think virus would never make sense on a hillside or other low-vigor location. The iconoclast position does have some attraction for me when applied to grapes in deep, fertile, valley floor soils with lots of sunshine and water.

Propagation via heat-treated cuttings is slow. It takes up to three years to develop generous amounts of stock when a new clone arrives from overseas.  A more modern technique is called Shoot-tip, or Mist Propagation. Although relatively more expensive, it does not pass along viruses, and it quickly produces considerable quantities of plantable material. Since 1995 the demand for planting stock in California has been so dramatic Mist Propagation has become very popular.

One big, and largely unanswered question is what effect viruses exert on the flavor of wine made from virused grapes. When Foundation Plant Services at UC Davis gets a new clone or variety, they assign an identifying number. Then they analyze for viruses, and use shoot-tip propagation to produce a virus-free version, which is assigned a different number. For example, the UCD clone 6 of Cabernet Sauvignon is the virus-free version of UCD clone 5, which originally came from a plot near Jackson (Amador County) which had been donated to the University in the late 1800’s.


LEES ~ Yeasts are plants. Yeast cells multiply by producing buds, which then cleave off the original cell. After a yeast cell has budded twenty to thirty times, it dies and sinks to the bottom of the container. These accumulating dead yeast cells are called ‘lees.’ The dead cells break open (autolyze) and release enzymes, which can have a number of effects on wine. For one, autolysis confers a baking bread smell, which is considered notably positive in sparkling wines.


LENGTH ~ A tasting term employed to describe the sensation that a wine’s aftertaste lingers in one’s mouth for a long time. Some wines are very intense with fruit in the nose, and may even make a very strong initial impression in the mouth, only to disappear quite abruptly when swallowed. Those wines are short. Lack of length casts doubt about the structural integrity of the wine. Length implies good acid. Length is generally considered a positive quality, although it should also be pleasant.


MACERATION ~ Term applied to time skins stay in contact with juice, must (fermenting juice), and/or wine.  Skin soak  is a subcategory generally applied to juice and skins sitting together prior to the initiation of fermentation (also called cold soak). ‘Skin soak’ is a phrase most commonly used in conjunction with white wines. Red wines, however, do often receive several days on the skins prior to beginning fermentation, and that procedure is more commonly called ‘cold soak.’ Similarly, the period during fermentation when CO2 raises skins to the top of the liquid, is generally referred to with the subcategory name punch down. That leaves ‘maceration’ to most commonly imply the period red wines stay on the skins after fermentation has ended.

Some red wines will be pressed off the skins prior to the very end of fermentation. That leads to softer, fruitier wines. It is not as messy in the barrels as one might anticipate, because the tumultuous phase of fermentation is early on. The graph of a fermentation is generally long and slow toward the end.

After the completion of fermentation, skins sink. ‘Punch down’ is no longer necessary to keep the skins submerged in the wine. Extraction of tannins and pigments will be more efficient at this time because of the solvent role played by the newly formed alcohol. CO2 is heavier than air. So it will sit on top of the wine and prevent oxidation, as long as it is not disturbed, and some sort of cap is placed on the tank. Many winemakers throw in a large piece of dry ice (solid CO2). Then strap down a heave piece of plastic as a cover.

Historically, time on the skins following fermentation for red wines has ranged from several days to more than three weeks. Long periods were always associated with wines meant for long aging. The extra extraction of tannins and pigments was thought to be extremely important in European districts where getting grapes ripe was a hardship. However, modern wine chemistry has revealed that long maceration time causes pH to rise. That gives you a softer wine with more polymerization (bonding) of the tannins and pigments.

Lastly, note that extended macerations take up tank space. That can be an important financial consideration. Tanks are expensive. Normal red wine fermentations (i.e. those allowed to go over 75ºF) take about a week. Call it 10 days maximum with some skin soak. Adding twenty days of extended maceration means you need three times as much tank capacity. Custom crush facilities’ managers don’t like that calculation very much.


MALO-LACTIC FERMENTATION ~ A bacterial fermentation in wine which converts malic acid into lactic acid, giving up a molecule of carbon dioxide in the process and creating diacetyl as a by-product. An effect is to reduce the perceived acid bite of the wine somewhat, and to confer a buttery / cheesy smell. Diacetyl is the compound used to make margarine (a solid form of vegetable oil) smell like butter.

It is a little ironic that MLF occurs most readily when it is unwanted. A Chardonnay at 3.20 pH is considered ‘biologically stable.’ That means it will not spontaneously go through MLF. Of course, very strong acid level is precisely when you do want your Chardonnay to undergo an MLF. So you have to inoculate with an acid-tolerant strain of bacteria, keep the temperature at about 70ºF, and maybe introduce some nutrients. If you visit a winery which has a barrel of wine covered by an electric blanket, they are trying to get an MLF started. Above 3.5 pH, malo-lactic is likely to occur spontaneously from the ambient bacterial load in the winery air. You might not want that. Sulphur dioxide, cold temperature, and filtration are the standard preventative measures.

Almost all red wines in California go through MLF spontaneously due to lactobacillus retained in the barrel wood from year to year..

When a winemaker in California says their Chardonnay had 75% MLF, they do not mean three-quarters of the malic acid was consumed, then they added formic acid to kill the bacteria. What they mean is they put ¾ of the wine completely through MLF, then filtered out the bacteria before blending with the remaining ¼ which had not undergone MLF at all.

An entertaining story highlights what a laboratory superstar winemaker Merry Edwards is. When she worked for Matanzas Creek Winery in the early 1980’s, they were making wine in an old milking shed on the property. Merry noticed their Chardonnays would spontaneously undergo MLF even at very low pH. Merry cultured the malo-lactic bacteria out of the concrete floor of the winery. Today MCW bacteria is a staple of the winemakers’ arsenal.


MARITIME CLIMATE ~ The opposite of continental climate, maritime climate means the difference between Average Daily Temperature in July and ADT in January is small ~ something on the order of 20ºF. It usually implies close proximity to a large body of water. Air changes temperature quickly. The surface of the land is slower, but it does change dramatically on a daily basis. Deep water changes temperature very slowly. So it lowers air temperatures nearby in the Summer and raises them in Winter. It does the same over a 24-hour period: lowering air temps in the afternoon; raising them at night.

In a maritime climate it is rare for an afternoon heat wave in Summer to get much above 75ºF. Central Coast vineyardists in California say, “Afternoon temperatures in Summer go up 1ºF for every mile you travel away from the ocean.” In Winter,Central Coast beaches rarely go below 45ºF over night, and they never freeze. These very moderate temperatures all year long mean the growing season is expanded. Vines bud in mid March, and grapes don’t need to be picked until rains come in December. French vineyard owners often speak wistfully about how desirable it is to get 100 days of sunshine between flowering and harvest. California’s Central Coast vineyards often get 180 days.

Contrast the temperature extremes in areas with a continental climate. Summer heat waves over 100ºF are commonplace, and often last for weeks. Winter overnight temperatures get to -10ºF all the time, and to

-25ºF with disturbing frequency. That’s a huge range. It’s hard on humans, even with our clothes and houses. It is a test for grape vines as well.



Two season climate ~ dry, hot Summers followed by wet, cool Winters ~ as opposed to the four season climate of northern Europe, which features freezing Winters, humid Summers, and distinct periods of milder weather in Spring and Fall.


MEDITERRANEAN DIET ~ A distinction contrasting traditional cuisine from warm southern European countries such as Spain, Italy, and Greece with historical cuisines from cold northern countries such as the Netherlands, Germany, and Denmark. Olive oil vs. butter; wine vs. beer; fresh fruit vs. sugared desserts; tomatoes, legumes, and herbs vs. preserved vegetables such as pickles and sauerkraut; seafood salads vs. charcuterie (patés, sausages); pastas with sauces vs. breads with eggs; eggplant vs. potatoes; citrus juice vs. cider. This contrast has everything to do with growing seasons, and with preserving food prior to the invention of refrigeration. It is not offered here as a medical recommendation.

In France the line of demarcation between these areas is even legally defined. It runs across the Rhône Valley south of Valence, separating the northern Rhône from the southern Rhône. North of the line it is legal to chaptalize wine, i.e. add sugar to raise the alcohol level as a way to help stabilize the wine. South of the line, grapes get enough sugar naturally due to increased sunshine.


MERITAGE (pronounced MEHR it tij, rhymes with heritage) ~ First, it is not a French word. So don’t say mehr it TAHJ. It is a word coined in California during a contest promoted by Dan Berger when he was wine columnist for the LA Times. In 1983 the Federal government increased the percentage of a grape required to use a varietal name on the label from 51% to 75%. People were just tired of getting wines called “Chardonnay,” which were actually 49% Thompson Seedless (the “Fresno Chardonnay,” actually a table grape). But opponents argued that some wines, such as Cabernet Sauvignon were better when blended with more than 25% of something like Merlot. If you couldn’t call a 70% Cab / 30% Merlot by the name Cabernet Sauvignon, wineries would have to spend fortunes acquainting consumers about proprietary names, such as Opus One, or Phelps Insignia.

The Berger contest had 6,000 entries, and was won by the name meritage, a generic phrase to describe blends of the Bordeaux varieties: (1) Cabernet Sauvignon, Merlot, Cabernet Franc, Malbec, and Petit Verdot for reds (now also allowing Carmenère and two others); and (2) Sauvignon Blanc and Semillon (plus Muscadelle du Bordelais) for whites. Meritage (with a capital ‘M’), however, is a trademark of the Meritage Alliance formed in 1988. They promote the name very successfully, but charge a license fee based on volume (it costs money to promote). The maximum fee is $500 per year. So you will often see ‘meritage’ used as a descriptive phrase on the back label, but only members of the Society can use ‘Meritage’ as a name on the front label.


MESO-CLIMATE ~ Basically the weather. Averaged over long periods of time, it becomes the climate. Other distinctions break it down into progressively smaller geographic locations. So you can have a generalization about California’s weather ~ that one is too broad to be of much use to anybody. Beware Vintage Charts that try to typify all of California as one place. Then you can have regional climate, such as Napa Valley, or the Central Coast. Now we’re starting to get useful information.

Macro-climate would be an area such as St. Helena or Calistoga. It is useful because it is small enough to give accurate information for people deciding on whether or not to carry a light sweater. It probably does not, however, supply enough information for a vineyardist deciding on which grape varieties to plant in his specific vineyard. That information would be called meso-climate, and it would be specific to his vineyard’s elevation, side of the valley, aspect, gradient, etc. So macro-climate data can be acquired at the local weather station (firehouse, airport, etc.) But meso-climate data needs to be acquired from one’s neighbors, or from one’s own equipment in the vineyard.

As an example, the fire station in St. Helena(on the valley floor) might report 0.75” of precipitation on 30 Oct. That gets recorded and entered into the macro-climate data for the district. A vineyard to the west on Spring Mtn at 1,600’ elevation might get 1.50” of precipitation that same day, while the vineyard you own at 800’ elevation east of town in the foothills of Howell Mtn probably only gets 0.30” of precipitation that same day. Accurate meso-climate information is important for vineyard management, even if it is not necessary for adequate umbrella management.

The phrase micro-climate is frequently misused by people who actually mean meso-climate. Micro-climate refers to weather on almost an individual vine level. Different aspects in one vineyard, for instance would create separate micro-climates. A row of tall trees that blocked wind and created shade patterns would similarly contribute to varied micro-climates. The citrus tree which survives next to a south-facing wall of your house, while an identical tree dies in the middle of the yard, would be further examples of micro-climate.


METHODE CHAMPENOIS (pronounced meth OHD SHAM pen wha) ~ The champagne method, largely a hand technique for getting dead yeast cells (lees) out of sparkling wine after they have conducted the secondary fermentation which puts bubbles (CO2) into the wine. Otherwise known as riddling (reumage) and disgorging the wine.

From the 1960’s through the ‘80s, there were four levels of sparkling wine made in America. The lowest priced wines were carbonated by injecting CO2 into a big tank of still wine, then bottling. Just like Coca Cola. A little more expensive were sparklers produced by the Charmat bulk process, commonly recognized today as the technique employed for Prosecco in northern Italy. This technique uses yeast to conduct a secondary fermentation in a large, closed tank. There are smell effects from the yeast, but they are mild. The third technique was called Transfer process. It involved a yeast fermentation in the bottle, then emptying all the bottles into a large tank, filtering out the dead yeast cells, and bottling.

Note all these methods avoid riddling the wine and disgorging it. Those are the heart of the champagne method. Riddling means gradually moving the lees down the side of the bottle onto the cork (actually a crown cap prior to disgorging). Riddling by hand with bottles in racks (the traditional champagne method) takes about six weeks and involves grasping each bottle 60 or 70 times. Thus the price difference between techniques. The upside from methode champenois is the wine in the bottle is subject to much longer influence by the lees ~ sometimes as much as eight years’ worth. There are considerable consequences for taste, smell, and texture.

Incidentally, in a feat of consumer legerdemain, those wines handled with the traditional methode champenois were labeled with a brief note, “Naturally fermented in this bottle,” while those handled with the transfer process were legally labeled, “Naturally fermented in the bottle.” Think average consumers ever noticed?

Gyro-pallets (GI)

After the lees have moved on to the crown cap (bottle upside down at this point) during reumage, the neck is frozen. The crown cap is removed. A plug of lees and ice blows out the mouth of the bottle (degorgement). The bottle is topped up with a tiny mixture of wine and brandy (which quiets foaming) called dosage. Any residual sugar the finished sparkling wine will have is added at this point as part of the dosage. Then the large cork is inserted and strapped down. All these processes of disgorging, topping up, and corking are automated. Riddling was not.

Today, technology has removed the expense of riddling by hand. That process is now done in large bins called gyro-pallets which move the bottles in unison automatically. For that reason, the Transfer process has virtually disappeared. It just doesn’t represent very much savings any longer.


MICRO-OXYGENATION ~ The mouthfeel of tannins in a wine can be made more supple by inducing the tannin molecules to bond together (polymerization) into longer chains. This bonding is accomplished by an oxygen atom at the linking point between two tannin molecules. Polymerization occurs naturally in the bottle over a long period of time, causing some tannins and pigments to become large enough to precipitate out of the liquid as sediment. Micro-oxygenation is the technique of bubbling oxygen through the wine at a calculated rate and quantity. It can be done quickly during fermentation to invigorate the yeast, or to correct reduction faults. It can also be done more slowly after the completion of fermentation (during the maturation period for the wine) in order to soften tannins and/or affect volatile characteristics of the wine.

Extended maceration is another technique which eventually softens the mouth-feel of tannins. Removing skins from the must (incompletely fermented wine) will result in a wine with less grippy tannins. If the skins are left in the wine after it goes dry, then, for a period of about three weeks, maceration will gradually increase extraction of hard, abrasive tannins. Then, counter-intuitively, the pH of the wine will start to rise, polymerization will increase, and the tannic bite of the wine will decrease.


MID-PALATE ~ When putting wine in one’s mouth during a critical evaluation (read tasting), there are three phases of reaction. The first one is called ‘entry’ (or ‘attack’ by the French). Entry is a set of descriptors which occur to one immediately. It is sensory input from the taste buds of the tongue and the tactile nerves of the mouth. It is a reaction to the structure of the wine, i.e. acid, tannin, residual sugar, body, etc.

The second phase is called ‘middle’ or mid-palate. A lot of people call it flavor. It is actually a combination of the reaction one gets to the wine’s structural elements (from taste buds) and the reaction one has to the smell characteristics of the wine as the wine is warmed in the mouth and the volatile constituents arrive at the olfactory cleft through the two openings at the back of the palate. You know this is true whenever you have a cold, and the two passageways at the back of your palate are clogged. In those circumstances you can evaluate structural features like acid or sugar, but you don’t get flavor. The smell component in flavor is by far the most important and complex part. There are only five taste sensations (sour, sweet, bitter, salty, umami), but thousand of smell sensations.

The third phase is called finish or aftertaste. That is the reaction you get once you swallow or spit the wine out. Does the sensation expand? Is it pleasant? How long does it linger? This last characteristic is called length, and it is an important indication of quality.


MILLERANDAGE (or SHOT BERRIES) ~ Pronounced mee arohn DAHZH. A condition caused by poor flower set in late May – early June (northern hemisphere) which results in some percentage of berries producing one or no pips (seeds) instead of two per berry. The size of these shot berries is dramatically reduced, as is their sugar content, making them quite acidic at harvest and reducing overall yield. The appearance of the clusters is described as, “Hen and Chickens.”

A propensity toward shot berries is a clonal feature, although the more proximate cause is usually rain (or hail) during flower set (florescence). Even cool or overcast weather can inhibit pollination, because the flowers don’t open completely.

Note that a modest percentage of Hen & Chicken clusters is not necessarily a bad outcome in warm California growing districts, as it will raise natural acidity and reduce alcohol. For that reason certain Chardonnay clones, such as ‘Mendoza,’ are occasionally sought by more radical CA vineyardists. In Burgundy, however, getting ripe is the fundamental problem underlying everything. So millerandage always reduces quality there.

Coulure (or berry shatter, pronounced coo LYOOHR) is the complete failure of fertilization, resulting in berries that are missing altogether. It can be caused by the same cold or wet weather conditions during flowering, or even by excessively hot conditions at that time. It can also be caused by overly fertile soil. Merlot, Grenache, and Malbec are particularly subject to coulure.

Shot berries


MORNING SUN ~ (cf: Evening sun) Vineyards which have an eastern aspect are common on the hillsides and benchlands of the western sides of California’s north-south running valleys. As the sun rises each morning above the eastern mountains, its rays shine directly into these westside vineyards. They get strong candlepower, but only during the hours of the day when ambient air temperatures are low. In the afternoon when temperatures are high, these vineyards are gradually shaded by the western mountains. This phenomenon can give wines made from these grapes a somewhat more lifted fragrance, even a floral note.

The other way morning sun can play an important role is in leaf-pulling at the end of the season to get more sunshine onto the clusters. If the vine rows are oriented north-south leaves can be removed on only the eastern side to provide morning sun to the clusters, but leave them shaded against the evening sun.


ORGANIC ~ Start by clearly understanding the difference between Organic wine and wine made from Certified Organic grapes. A vineyard which sees no synthetic fertilizers, no pesticides, no herbicides, and no mildicides for three years can be Certifed Organic. There are a number of certifying agencies. California Certified Organic Farmers (CCOF) is the biggest in the state. Wines made from those grapes can legally say “made from Certified Organic grapes” on the label. But it is not Organic wine. The distributor salesman will often say it is, and may occasionally put up handwritten shelf-talkers saying “Organic Wine.” That claim is untrue, but mistakes happen. The salesman is probably just ignorant, not sneaky. Retail salespeople may say the wine is Organic. They are legally wrong. They just don’t know better.

Organic grapes go in the winery door, but who knows what chemical atrocities may be committed inside the winery?

The Food & Drug Administration (FDA, part of the US Health Dept) is responsible for regulations concerned with calling a wine Organic on the label. There aren’t very many of those wines because one of the US requirements is no added sulphites. That’s a very tough regulation, and not one you would find in Europe. So you see ten times more “organic” wines in Europe than you do in America ~ they just have a lot of SO2 in them.

True Organic wines in America are a very specialized business because low SO2 environments require an absolute minimum access to oxygen. A handful of makers do a pretty fair job, but most of them will tell you they are better with reds than whites, and don’t hang on to bottles very long ~ a year or two at the most.


OXIDIZED ~ Half of a reversible chemical equation (called redox, i.e. reduction-oxidation) in which electrons are lost by certain compounds (oxidation) and simultaneously gained by other compounds (reduction, because electrons are negatively charged).

In general we think of oxidative reactions as a wine ages or spoils. It is occasionally hard to draw the boundary line between these two conditions. One man’s idea of ‘development’ in a wine to another man is rank oxidation or spoilage. Aging involves the gradual oxidation of a wine such that secondary smells (a form of bouquet) are produced. Aldehydes, which smell nutty, are an example. They result from adding an oxygen molecule to ethyl alcohol. Most people consider the complexity added by aldehydes to be a benefit, particularly in red wines. If the wine has unlimited access to oxygen though, the aldehyde adds another oxygen molecule to become acetic acid. That’s vinegar. Now, in low concentrations even acetic acid has its fans. It raises complexity and helps bring fruity smells out of a red wine. As the concentrations get higher though, fans start exiting the bus. Eventually the acetic acid bonds to the ethyl alcohol to form ethyl acetate. You would know that as finger nail polish remover. At this point the wine is well and truly cocked up.


pH ~ General indication of acidity in a wine or in grapes. Technically, however, pH measures how much the acid molecules have dissociated (i.e. separated into charged ions), and are therefore available to react with other things. Think of it as if you were throwing a party. You invite ten men and ten women. In one instance nine of the men and nine of the women are couples. In another instance six of the men and six of the women are single. Clearly the potential for fistfights and unwanted pregnancies is much greater in the second instance. It is a more reactive situation. The number of acid molecules (male-female pairs at the party) is the same in both instances, but the ‘strange’ hook-up potential is greater in the second example. That would be the case of a more extreme pH.

The pH scale can be a little confusing, because it appears inverse to Total Acid. The pH scale has 14 units. Seven is neutral (like distilled water). Low numbers indicate increasing acidity. High numbers indicate increasing alkalinity. So soap would be around 9, and sodium hydroxide (lye or Drano) would be 13.7. Stomach acid is about 3.4. So is most wine, incidentally. Sulphuric acid would be 1.1. A wine measuring 3.9 would be ‘flabby.’ A wine measuring 3.1 would be very sharp (and hard on your tooth enamel).

pH is related to Total Acid, but they don’t always move in lockstep. Buffering compounds in a wine can mean a shift in Total Acid doesn’t always create a corresponding shift in pH.


PHYLLOXERA ~ Phylloxera Vastatrix is a  root louse, native to North America. The many American species of grapes, such as Vitus labrusca (Concord) and Vitus rotundafloria (Muscadine) have all evolved resistence to Phylloxera over tens of thousands of years of exposure to the root-eating insect. If they had not, they would have died out. The single European species of grapes (Vitus vinifera) didn’t have that evolutionary exposure, so its roots are subject to depredation if Phylloxera is present. The insect does not like sandy soils, and does not over-winter successfully in cold environments.

During the late 1850’s grape plant material was taken from the US to Europe. There were Phylloxera bugs on the roots, which then escaped into a virgin landscape full of susceptible vines. Between 1860 and 1890 more than 90% of Europe’s vineyards were destroyed. Ultimately the fix was developed by a French plant physiologist (J.E. Planchon) and an American entymologist (C.V. Riley). A grape breeder and promoter from Texas (T.V. Munson) also played a very important role. The answer was to graft resistant rootstock from the wild American grape Mustang onto V. vinifera scions (tops). It is probably unnecessary to point out this solution was not terribly popular amongst nationalistic French growers. It took a considerable amount of political arm twisting to get the scheme implemented.


PIERCE’S DISEASE ~ Systemic bacterial disease (Xylella fastidiosa) affecting grapevines in many areas of the US. Particularly troublesome in Texas. Spread in the spittle of a winged insect called a Sharpshooter, which commonly over-Winters in citrus and/or oleanders. Named for Newton Pierce,California’s first plant pathologist, who identified it in 1892.

The bacteria damages a grapevine’s xylem layer at the point the Sharpshooter has been sucking sap. This damage then blocks water and nutrients from flowing up to the leaves. If recognized early, the damaged section can be removed, saving the vine. Otherwise the disease is fatal.

Muscadine (Vitis Rotundifolia) grape varieties, from the Southeast US, are resistant to the bacteria. A situation which introduces both a technical solution, and a political problem. Genetic modification might well be possible, but would it be acceptable in the marketplace? Current research is focused on classical breeding techniques which hybridize vinifera vines with rotundifolia vines. After some five rounds of crosses (15 years of interbreeding), seeds which are 94% high-quality vinifera were planted in 2007. We’ll see. Wine trials are just beginning. Muscadine aromatic properties can be pretty intense. Is this methodology really better than inserting the rotundifolia gene for PD resistance into a vinifera vine? Which is research that can be done for a fraction of the money spent today trying to quarantine Sharpshooters. The gene goes from one grape into another. It’s not on the same order of weirdness as taking a fish gene for cold resistance and putting it into a tomato.

(See Pierce’s article on Bruce Cass Wine Lab site).


PIGMENTS ~ Anthocyanins found in the skins of black grapes, and polyphenols called pigmented tannins. Extracted along with other tannins during the maceration process. Together, tannins and pigments form the bulk of the dry extract in red wines. Pigments need to become bound, either to tannins or to long chain sugars (polysaccharides) in order to make red wines color fast. Malbec, for example, often benefits from at least a small admixture of tannin rich wine (Cab Sauv, Tannat) to fix the color and to confer longer-term ageability.

The number of different anthocyanins varies by grape variety. Pinot Noir has the fewest. Hence it is always the lightest colored of red wines. Petite Sirah has the most.


PROPRIETARY NAMES ~ Names for wines which are made up, and owned, by the winery using them. So ‘Cabernet Sauvignon’ is a varietal name (grape variety), and the winery must be able to document that 75% of the juice in the wine came from Cabernet Sauvignon grapes. ‘Claret’ would be a generic name in the US. Lots of wineries may use it, but there are little or no restrictions on what grapes go into it. Imagine how it sours US-France diplomatic relations when California wineries use ‘Burgundy’ or ‘Chablis’ as generic names for inexpensive plonk! ‘Champagne’ is a particularly egregious example of this place name abuse.

‘Bocadanse’ could be an example of a proprietary name. The winery that coined it could put any combination of grapes in it they want ~ and change the combination every year if they want. Actual examples include Trilogy (Flora Springs), Maya (Dalla Valle), and Dolce (Ch. Chevalier). The winery owns the name. They have to explain to consumers what it means, but no other winery can use it. Of course wineries also have to incur some legal expense to defend their ownership. Charles Kreck at Mill Creek Vineyards in Sonoma was the first one to use the phrase ‘blush’ on a light-colored wine made from red grapes. He trademarked the name in 1978, but chose not to defend the trademark, instead letting the phrase become a generic name.


PUNCH DOWN ~ Term refers to a specific technique, during fermentation of red wines when CO2 is raising skins to the top of the fermenting juice, whereby the skins are re-immersed into the liquid. This result is important for two reasons: (1) extraction of pigments and tannins will only occur when the skins are immersed in the must (fermenting wine); and (2) skins sitting on top of the liquid are a fertile medium for the growth of acetobacter, which cause spoilage of the wine. Depending on the ratio of height to diameter in the fermenting tank, skins can form a cap on top of the fermenting liquid which is 12” to 18” thick. That is why tall, thin tanks are white wine fermenters, i.e. no skins. Red fermenters are wider and shorter.

Several different techniques can achieve the general result desired:

- Pigeage (pronounced pee jhay AHJ) assumes an open-top fermenter. If the fermenter were only waist high, one could climb in and thrust the skins to the bottom with one’s feet.  It looks like fun, and it is… for about five minutes. Then it is work, and each tank takes about 45 minutes. Barefoot, however, pigeage is the most gentle of these techniques.

- Punch down also assumes an open-top fermenter. Wielding a 6’ long device that looks like a piston, i.e. long bar with a 12” to 18” flat plate on one end, the winemaker physically shoves the skins to the bottom of the tank. It is really hard work. As an example, I weigh more than 275 lbs. In a 10-ton fermenter at the beginning of the session, I can stand on the punch plate (on top of the skins) without sinking in. It takes a lot of strength, and about half-an-hour to punch a single tank. That is one reason hydraulic punching devices make good sense. Punch down is not as gentle as pigeage, but it is more effective than pump over.

- Pump over is the most widely practiced technique. It involves pumping wine out of the bottom of the tank and then spraying it through the top of the tank onto the skins. Pump over clearly aerates the wine more than other techniques, which can be a positive when H2S is a concern. It is not as effective at tannin and pigment extraction as punch down. One major advantage of pump over is its applicability to large tanks (over 10-ton) which are not open top. Equally important, pumps can be computerized to perform pump overs without staff late at night. With a computer and a pump, the winemaker (and owner) know the task was actually performed. Low level staff are perhaps not quite as trustworthy when it comes to 3:00 am punch downs.

- Délestage (pronounced day luh STAHJ) sometimes called rack-and-return, is a technique of taking all the wine out of a tank, letting grape solids and seeds sediment out, then returning the fermenting wine to the skins. This technique works well on large tanks, has the advantage of only needing to be done once per day, and avoids certain harsh and bitter tannins which come from seeds. Thus wines are pleasurable to drink earlier. The downside is délestage requires an extra, unoccupied tank.

- Screens, to hold skins under the surface of the liquid, are another perfectly logical technique. I’ve not seen them much in modern wineries, but they were used ~ redwood lattice ~ in several early (1900’s) Zinfandel fermenters.

- Rotofermenter is a big piece of equipment which looks like a cylinder on its side with hatch on the top. The whole shooting match can be rotated (with the hatch closed) to re-immerse the skins in the must. Rotofermenters are very effective at extraction, great for large lots, but not very gentle.

The other important factor pertaining to punch down is frequency. Twice a day is not very effective, but it is reliable. Three or four times per day is what one would want for effectiveness. That frequency involves the expenditure of a great many calories, and some really long hours without sleep.


PYRAZINE ~ Phrase used generically in reference to a large group of organic compounds which have strong smells, even in very small concentrations. The methoxyprazines are noted for a Bell pepper smell. Sauvignon Blanc, and its genetic offspring Cabernet Sauvignon, both contain pyrazines which metabolize as the grapes get riper. Hence cold climate Sauvignon Blanc will show a strong jalapeno smell, which can be muted to a mild grassiness (often described by British writers as gooseberry or cat pee) by techniques such as leaf pulling, which gets more sunshine onto the clusters and increases ripening. Increased ripening in turn progresses along this range of smell to a metallic, stony character. Finally, when all the pyrazine is metabolized away, Sauvignon Blanc takes on a melon-like smell.

This ripeness progression makes Sauvignon Blanc an interesting wine for comparing various regions to each other. In Cabernet Sauvignon the presence of pyrazine is often a good indicator of ‘shaded canopy’ trellising techniques (see VSP).


RACKING ~ Winery process whereby clean wine is siphoned off sediment (usually lees, but can also include pulp and tartrate crystals) in a vessel like a fermentation tank or a barrel. The clean wine is then put into a different container so that the original one can be cleaned. Racking tends to introduce some air to the wine, which helps to remove sulphides. So it is routinely done a couple times per year. It also affords a good opportunity to accomplish blending goals, or to change the barrel environment (say, from newer to more neutral) in line with a winemaker’s preferences.


RAIN SHADOW ~ When the prevailing pattern of rainstorms comes from one direction, and passes over a mountain ridge, the clouds rise. In the process they cool (4ºF for every 1,000 feet of elevation), condensing the water, which falls as rain drops on the mountain slopes. As the clouds continue on, the next landscape encountered receives much less rain. It is said to be in the rain shadow of the mountains.

In California this phenomenon occurs in many places because the storms predominantly come from the Pacific Ocean traveling west to east. In Napa Valley the rain falls much more heavily in the Mayacamas Mountains on the western side than it does in the Vaca Mountains on the eastern side. One can easily see that distinction. Stop in Oakville or Rutherford on Hwy 29. Look to the west. The mountains are covered in conifer forest. Then look to the east. Those mountains have a lot of chaparral (brush), but very few trees.

In the Sierras, ski resorts on the western slope get wetter, denser, heavier snow than do resorts on the eastern slope, which are known for less snow, but colder, drier powder snow. A good illustration, on a virtual line from west to east, all in California, would be the large amounts of wet snow at Sugarbowl on the western slope, medium amounts and water content at Squaw Valley on the peak, then the powder of Northstar on the eastern slope.

Same in South America. Valparaiso, Chile (on the coast) gets 18.5” of rain per year. Santiago, Chile (east of the 7,000 ft coastal mountains) gets 12” rain per year. Mendoza, Argentina (just east of the Andes) gets 8” per year (technically a desert). Cafayate, at 5,000 feet of elevation in the Argentine Andes only gets a couple inches of rain annually despite its elevation, because it is in the lee of 20,000-foot peaks.


RED LEAF VIRUS ~ Also called Leaf-Roll virus, is actually a suite of systemic viruses (around 60 have been identified so far) which can show up in various combinations in grape vines slowing maturity and affecting color of the grapes, reducing production, and imparting a distinctive color change to the foliage at the end of the growing season. The viruses move very slowly from vine to vine, and are thought to be transmitted by a pest called a mealy bug. It may well be that different vectors (e.g. aphids, nematodes, mealy bugs, mites. etc) may transmit different viruses. In California, virus is easy to recognize by mid October. Leaves of non-virused vines turn brown, starting closest to the trunk. Then they fall off in a progression moving outward. The leaves of virus-affected vines turn dark red (black grapes) or bright yellow-orange (white grapes) at the end of the season, often starting from the tips of the vines, and stay on the vine longer. It’s a phenomenon related to the Autumnal foliage change in trees.  It is visually arresting as it decorates certain parcels of a vinescape.

Red Leaf Virus

Primarily because of the reduced production issue, UC Davis decided in the 1960’s to eradicate virus in California vineyards. They were largely successful. Today, well over 95% of California vines are “heat-treated, virus-free.’ The original technique was to put vine cuttings into sand, which was then kept at 120ºF for about six weeks. These Certified vines are then propagated and sold through licensed nurseries. It’s a good technique, compared with taking cuttings yourself from a vineyard you admire, because it doesn’t add much to the cost, and you gain quite a bit of confidence concerning the varietal and clonal identity of your new plants.

Heat-treated cuttings do require three years to grow out any volume of plantable material though. Demand for new varieties and clones can get feverish when vineyard acreage is expanding as rapidly as seen in California from 1994 through 2013. Answers include a technique called macro-shoot-tip, mist propagation. This technique requires greater expertise and more expensive equipment, but it also eliminates viruses, and produces a considerable quantity of plantable material in six months. Needless to say, since about 2007 it has been all the rage in California. An even finer technique is called micro-tissue-culture. That involves dissecting growing tips under a microscope, and growing them in vitro. It also eliminates viruses, and is the technique UC Davis uses today for that purpose.

This concept of ‘virus-free’ vines is not universally endorsed, however. All the big money endorses it, and all the people trained at Davis do, but there are a few iconoclasts (mostly with European training) who say, “If California wines suffer from high alcohol, low acid, and over cropping, why wouldn’t I want a micro-biological policeman in the vineyard keeping production and Brix levels down to more reasonable levels? Especially when I’m buying grapes from a grower I don’t control.” Davis-trained viticulturalists reply, “Tuberculosis would make you thin like a supermodel, but it would not be a good idea.” The iconoclasts follow up their argument by calling heat-treated vines “bull vines,” which can not be restrained. They say the ‘virus-free’ vines, when planted on fertile, valley-floor soils and irrigated, put out 20 shoots per cordon even when you prune back to 8 spurs. And, if you drop 12 of those shoots, the ‘virus-free’ vine will set 4 clusters per shoot instead of two. Then, if you cluster thin, you get “basketball” berries.

I’m not entirely on-sides with the iconoclasts. I think you’d be nuts to want virus in a hillside vineyard. And I think you want to look to vine spacing and to rootstocks in a vigorous vineyard location long before you entertain virus as a beneficial tool. But don’t immediately dismiss vineyard properties which have a little virus either. In all likelihood they will be older vines, and my experience says they may very well make some wonderfully complex wines.

Which brings us to the main, and largely unanswered question: Does virus in a grapevine affect the taste of the wine, other than structural characteristics (like body and acid) which are due to ripeness? The Foundation Plant Material Service at UC Davis is a repository of genetic material which will probably have an authoritative position on this matter one day. Right now, when they get a new clone of a grapevine for their collection from somewhere around the world, the first thing they do is clean up the viruses to create a virus-free version. Then they assign that virus-free version a different ID clone number. So, for instance, the scraggly-clustered, small-berried Cabernet clone from the very old vineyard up in Jackson (Amador County) UC was given at the end of the 1800’s is called UCD #6. That one would be the ‘heat-treated, virus-free’ clone. UCD #5 would be the version from the same mother vine, albeit still containing viruses with which it arrived, when they took cuttings for the collection in the 1960’s. You’ll not be seeing UCD #5 on any nursery offering sheet. By the way, UCD Cab #6 produces low cluster weights, and low individual berry weights, thus lower productivity than other Cab clones, even without the viruses.


REDUCED ~ Chemical reactions that occur in an atmosphere deficient of oxygen. These reactions and the compounds formed are atypical of standard winemaking practice, but that does not necessarily make them bad nor distasteful. Moreover, when exposed to air (oxygen) the chemical reactions reverse, and they move toward the oxidative side of the equation.

One common reductive reaction is found in Sauvignon Blancs, usually right after they have been released. They have a smell, often referred to as an underarm smell, which I think is very similar to malathion (aphid spray). It goes away with aeration ~ severe and prolonged swirling of one’s glass ~ and disappears from bottles within about 6 months.

Sulphides are another issue attributed to reductive conditions. That’s not an entirely accurate description, because sulphides don’t stem from the redox reaction, they are produced by yeast when insufficient oxygen is available to drive metabolism


ROOTSTOCK ~ The bottom half of a grafted vine.

Rootstocks took center stage when 90% of European vineyards were wiped out between 1860 and 1890 by a native American insect called Phylloxera vastatrix, a louse which eats vine roots. Native American species of grape vines have evolved with phylloxera. Hence are resistant to it. If they weren’t, they died out long ago. So two French plant physiologists, and one from Texas (T.V. Munson), co-operatively developed a rootstock from Mustang vines growing wild in Texas. It solved the problem. French vineyardists were understandably hesitant at first. Eventually financial pressures brought everyone around.

In California the most popular rootstock from Prohibition to the 1990’s was called AxR1 (Aramon crossed with Rupestris, the first a – r cross done by the French hybridist Ganzin). It was famous for increasing production, and was strongly recommended in California by county farm advisors, who are part of UC Extension. Despite the fact UC professor A.J. Winkler’s classic textbook General Viticulture published in 1962 states of AxR1, “That its resistance to phylloxera is not high has been demonstrated in other countries.” Criticism about phylloxera susceptibility, because Aramon is a vinifera variety, was regularly voiced, and largely ignored. Ninety percent of Napa Valley was planted with AxR1. Then phylloxera was discovered in Napa Valley at the end of the 1980’s. It moves slowly, and doesn’t kill vines overnight, but replanting was a half billion dollar problem.

Today Napa is pretty much replanted. Moreover, replanting afforded Napa viticulturalists an opportunity to rethink varieties, clones, spacing, vine training systems, and rootstocks. Modern vineyardists choose from among 30 or 40 rootstock options. Different rootstocks emphasize drought resistance, production vs. low vigor, nitrogen uptake, preference for soil porosity, tolerance to nematodes or to virus in the budwood, soil pH preference, performance in dense plantings, etc.


ROW ORIENTATION ~ The direction trellised vine rows run.

It depends on a lot of things, but in California it usually comes down to the shape of the property, and trying to fit in the longest rows possible. Certainly that would be true if the grapes were going to be mechanically harvested. The second consideration might be erosion, and whether terraces would be necessary. Planting legumes and grasses to hold soil in vine rows running up and down a hill, however, is a much more robust technique than most people realize. Carving terraces with a bulldozer at the wrong time of year can cause severe erosional damage.

In high latitudes (over 40º north or south) there is an advantage to orienting rows north and south so the sun will shine equally on both sides of a VSP curtain. If the rows run east & west, one side (south side in the northern hemisphere) gets most of the sun, and clusters on that side ripen weeks ahead of clusters on the other side. That requires hand picking ~ first the sunny side, then the shaded side two weeks later. The Okanagan Valley of British Columbia is a steep, glacier-carved cut running North to South. There is very little harvest labor force, and few flat sections to plant. Mechanical harvesters must run up and down the sides of the valley (i.e. east – west). If they tried running parallel to the sides of the valley (i.e north-south), they would tip over. So vintners in Okanagan are stuck with paying enormous costs for hand picking, or making wine from grapes that are half over-ripe and half under-ripe.


SAIGNÉE ~ (pronounced sawn YEAH) Winemaking technique which translates from French as “to bleed.” Must (partially fermented juice) is drawn out of a fermenting tank after just a few hours on the red skins. Therefore the remaining juice gets increased color and flavor from a greater concentration of skins to must.  The removed portion is made into a rosé wine, usually sold as Vin Gris.


SAMPLING VINEYARDS ~ In northern Europe, deciding to harvest a vineyard is frequently a function of freezing weather. The decision is made for you. In California, however, it is always an opinion based on how ripe the grapes are. An opinion because vineyard ripeness is more difficult to ascertain than you might imagine.

A vignette will illustrate. Every Zinfandel winemaker has a horror story about bringing in a load of grapes from a vineyard you’ve not used before. The grower said the grapes were 24ºBrix. The grapes are crushed into a fermenter, and the winemaker measures sugar at 25ºB using an hydrometer (little floating gauge that measures specific gravity). All seems pretty reasonable, so the winemaker lights it up (puts his fermenting yeast culture in). He goes home for the night, returning next morning expecting the sugar to have gone down to 22º or 23ºB as the yeast starts converting sugar to CO2 and alcohol. YIKES! The sugar is now 27ºB. That means we’re looking at 16.5% alcohol and 3% residual sugar! There is nothing for it but to employ the ‘Black Snake Fix,’ i.e. turn the water hose on the fermenter to dilute the sugar down a bit. What could have happened? Well… Some of the berries were raisined. They didn’t release their sugar into the juice until they had soaked over night.

The reason vineyard ripeness is so hard to determine is vines in different parts of the vineyard will ripen at different rates based on vine age, water-retentiveness of the soil, crop level, grape variety, etc. Clusters on different parts of a single vine will ripen at different rates depending on sun exposure, distance from the trunk, etc. Finally, berries in different positions on a single cluster will ripen faster or slower than other berries. The ripeness of the crop, the Brix and pH numbers in the wine, will be the overall totals for ALL the berries mixed together. So one might wait until all the grapes are de-stemmed and crushed, then measure Brix and pH in the fermentation tank. At that point, however, it is too late to do much about the situation.

Better to sample the vineyard every couple of days for two weeks before harvest. That way you can create a record for how rapidly this particular vineyard ripens. You can schedule a picking crew more adroitly, or juggle the timing of various vineyards as necessary. You can perform various interventions, such as picking selectively multiple times, or applying some irrigation water to slow ripening, or pulling some leaves to get more sun on the clusters.

Sampling is a bit of an art form. The idea is one person walks through representative parts of the vineyard with a plastic sandwich bag taking a total of at least 300 single berries from random parts of random vines. The berries are then all mooshed up in the bag and the juice analyzed ~ which can be done on the spot with a refractometer (device, about the size of a robusto cigar, which reads sugar level by noting how much a beam of sunlight is bent as it goes through a drop of juice) and a pH meter. The problem is getting humans to grab ‘random’ berries. Everybody tends to grab ‘good lookin’ berries. And only the most dedicated samplers get as many berries from underneath vines, and inside clusters, as they do from outside edges of waist-high clusters. Nobody samples with ruthless accuracy, and rarely do two people achieve the same results when they sample. One thing that does help, an individual often samples with a constant inaccuracy. So after two or three years experience with a particular vineyard, a specific individual can ‘adjust’ his or her sample results to be fairly accurate.

Sampling takes time, especially when travel to remote vineyards is factored in. There is a lot of value though. Sampling lets the winery assess the condition of the grapes. That is not information one expects to get without some degree of spin from the vineyard owner. Same with pH and Brix levels. Vineyard owners always want to pick quickly, get the crop off the vine before anything goes wrong, and get paid. Waiting for more maturity is always the position of the winemaker; never the vineyard owner. Relying on pH and Brix numbers from a vineyard owner is like believing statistics offered by a politician. You’re just asking to have the wool pulled over your eyes.

Which brings us to the concept of the winemaking über consultant; the guy who has 20 prestigious clients on two or three continents. There is no way that guy is driving for an hour or two each way to sample a vineyard multiple times before harvest. Maybe a vineyard at the winery, but way-the-hell-and-gone up in the mountains? Not in this lifetime.


SCREW CAPS ~ Often called Stelvin closures, after one of the prominent brands. Screwcaps have become very popular in New Zealand and Australia because winemakers there are convinced the rate of corked bottles may be as high as one in twenty. People on the production side of the wine business generally think screwcaps are a very good technical solution to a significant problem. Screwcaps are not cheaper. One’s first glance objection is often that they do not allow any air to get into the bottle ever, and that therefore wines will not age with screwcap closures. Fifteen years of research in Australia has disproved that theory. Look at a screwcapped bottle. It is the same size as a bottle that takes a cork. Hence the space that was previously occupied by the cork is now an extra dose of air (read oxygen) inside the bottle available for gradual development of the wine.

Marketing people in the wine industry generally come down on the opposite side of the issue. Prior to 2010, screwcaps were a marketing problem. The US probably represented the biggest restraint on wide adoption. The reason is so much inexpensive jug wine came out of CA’s Central Valley during the ‘60s and ‘70s closed with screwcaps. It was a uniquely American phenomenon, and actually demonstrated the enormous technical sophistication of Julio Gallo, but it did fix screwcaps in the mind of American consumers as belonging to the jug wine category.

(See blog on alternatives to natural cork closures.)


SKIN SOAK ~ Sometimes called cold soak. Winemaking technique of leaving skins and unfermented juice together in a fermentation tank for some period prior to initiating the fermentation by adding yeast (“Light that tank up!”). Cold soak for many red wines might occupy three days and involve putting SO2 into the juice to inhibit wild yeast. Cold temperatures (below 48ºF) also inhibit yeast. It is a common practice these days for red wines to utilize cold soak. The practice was first popularized by legendary Burgundian winemaker Henri Jayer. It was then expanded during the 1980’s by Jayer’s accolyte, the consultant Guy Accad. Of course, it is advisable to have as perfectly clean grapes as possible.

The practice is less common in white wines, with Chardonnay being the variety on which it is most frequently utilized, and 18 to 24 hours being pretty much the upper limit of duration. Skin soak adds body and fruit complexity to Chardonnays by taking some extractive compounds from the skins, and a lot of flavoring material from the mucilaginous layer between the skin and pulp. Dangers arise from mold on the grapes, or from wetable sulphur on the skins (having been sprayed to inhibit mold growth after a rain). Sulphur on the skins can lead to hydrogen sulphide (H2S) in the wine. Skin soak can also make Chardonnays harder to clarify.


SPIT OUT WINES ~ Winemakers taste all day long by spitting wines out. The generally aim for a drain in the floor. Most of them will gain respect for your sophistication if you do the same. They will recognize your interest in taste over intoxication. Moreover, the ability to expectorate wine adroitly is impressive to anyone in the industry. It is like a secret fraternity handshake. The idea is to maintain a tight pattern on the target. You can practice in the shower. The key is loose lips. While developing your expertise, you should probably plan on close proximity to the receptacle. In elegantly furnished tasting rooms, it may be wise to step outside and anoint some of the landscaping. Tell the gardener you are driving.

SPLIT CANOPY ~ Trellising technique which utilizes two parallel cordon wires about 30” apart to support a larger canopy, and to open up the middle of the canopy to allow more penetration by sunlight. Applicable in highly productive conditions: deep soils, fertile soils, high water table, water retentive soils.


SULFIDES ~ Most prominently Hydrogen Sulphide ( H2S ). A ‘rotten egg smell,’ which in high concentrations many people equate with ‘baby diapers.’ It forms in the reductive conditions of yeast fermentation, especially if wetable sulphur has been sprayed on the grapes just prior to harvest as a means of preventing mold. Lack of nitrogen is a contributing factor, and certain varieties (e.g. Chardonnay) or vineyard sites can be deficient in nitrogen. Once recognized during fermentation, H2S is easily corrected by aerating the wine because the gas is so volatile.

H2S formed subsequent to fermentation can be a more difficult problem, but it is usually amenable to a copper sulphate addition. Certain yeast strains tend to produce H2S when they autolyze (i.e. die and break open). In those conditions H2S frequently combines with other compounds to form mercaptans (the same compounds put into natural gas so we can smell it in case of a leak), thiols and disulphides. These compounds smell (variously) like cooking cabbage, garlic, sautéed onions, and burning rubber. In small concentrations they can add to the complexity of a wine, but once the concentration passes an individual’s threshold for recognition, they are universally considered faults.


SULPHUR DIOXIDE  (SO2)  ~  Irritates the mucus membranes of the nose and eyes. Is generally added to wine in the form of potassium metabisulphite which releases sulphur dioxide. Hence the warning label on wine sold in the U.S. “contains added sulfites.” (Spelled ‘sulphites’ overseas for bonus confusion.)  SO2 is more of a tactile sensation than it is a smell. Imagine a match being struck right under your nose.

Free SO2 is what you notice. Eventually (6 mo to 2 yrs) it will become bound into the wine ~ combined with other molecules. Then you won’t detect it while tasting the wine. Free SO2 will also ‘blow off’ somewhat if you swirl the wine in your glass vigorously.

Sulphur has been burned (forming SO2) inside containers for thousands of years as a means of preserving wine and other foodstuffs. In wine it acts as an antioxidant, and additionally will inhibit or kill wild yeast and bacteria. All wines contain some sulfites, because it is a by-product of the yeast fermentation, but these naturally occurring examples are usually under 10 ppm. To label a wine ‘organic’ in the U.S. no sulfites may be added. The European Union has no such regulation for their “organic” wines, and this discrepancy is highly controversial.

The Sulfite Warning regulation on wines sold in the U.S.was introduced to Congress by one of the younger Kennedys in the late 1980s. The theory is that it protects consumers with serious asthma problems. Of course every salad bar in America has a solution with 300 ppm of free SO2 sprayed on it to keep the lettuce from turning brown, and rarely is a CA wine made these days with more than 40 ppm of free SO2, but that’s federal regulation for you. Don’t get me started on the sulfite content of dried fruit sold in Whole Foods. Ironically, CA winemakers are now very leery of SO2 (perhaps because of the warning label requirement), while European winemakers routinely use much higher levels on their wines (200 ppm is not unheard of).

Any California wine sold in Europe must cover up its Sulfite Warning on the bottles (also the Surgeon General’s warning about pregnancy issues and driving heavy machinery while drunk), and a European wine sold here must apply a warning label.


SUR LIE ~ French phrase for wines matured in a container with some volume of the dead yeast cells (lees). Yeasts are plants. They reproduce by budding. After the have budded 20 to 30 times they die, sinking to the bottom of the container in the case of a wine fermentation. A large volume would be called the gros lees, while several days later a mild sprinkling would be called the fine lees. When yeast cells die they autolyze, or break open, spilling enzymes into the wine which confer a smell (not unlike baking bread) and flavor to it. These enzymes also give the wine an added texture, usually described as creaminess. Standard procedure would normally be to siphon clean wine off the top of the lees, a process called racking. Leaving lees in the wine to add a flavor and textural component is an historic Burgundian method referred to by early California practitioners as one in a suite of “filthy French techniques.” Use of wild yeast would have been another example.

Nevertheless, sur lie aging has become fairly common for certain wines such as high-end Chardonnay in California. One of the dangers of sur lie aging is that in a thick layer of lees, those cells on the bottom without any access to oxygen (a reductive environment) will begin to produce H2S. Top winemakers at small wineries, who have their nose in every barrel every month, feel confident they will recognize this problem while there is plenty of time to fix it (by aerating the wine). But there are also precautionary techniques which can be employed: (1) battonage involves inserting a little stirring device (Guth is a brand name for one that employs a small propeller) into the barrel through the bung (hole in the top) and stirring up the lees periodically; or (2) barrels can be rolled back and forth about halfway around in order to distribute fine lees evenly in a thin layer over half the barrel’s interior surface.


SUSTAINABLE ~ There are vineyard owners and wineries who sneer at ‘green’ practices. Then there are people in the wine business who strongly endorse the concept of ‘green’ practices, but who do not think there is much financial advantage, and who want to keep their options open against the possibility of something like a huge leafhopper infestation some year. Many organizations have taken up the mantle of ‘sustainability.’ On the one hand it services those sympathetic individuals who don’t want their hands tied. On the other hand it serves as an educational tool to bring the sneer constituency slowly around. And, of course, the PR potential should never be ignored.

Sustainability programs, of which there are many, would be the third level of rigorousness in terms of compliance keeping chemicals out of the winery and vineyard operations (well behind Certified Organic, and Certified Biodynamic). Sustainability programs, however, reach more broadly into ‘green’ practices such as water conservation, wildlife habitat, and alternative energy generation. Furthermore, sustainability programs are the only practice addressing social issues such farm worker pay and the politics of immigration. Basically sustainability programs are all about participants gradually improving their green performance across the board. Enforcement is not a key feature, and the emphasis is not on bars which need to be cleared with any urgency. Requirements are set to attract participants; not to exude a ‘holier than Thou’ attitude. There are dues, attendance at several meetings, and one is expected to display a positive public demeanor on the subject of ‘green’ initiatives. Sustainability programs are a good thing, even though they are usually run in conjunction with a regional promotion guild. Sustainability programs bring by far the largest audience to the ‘green’ table, and California has several very successful examples.


TANNINS ~ Large group of compounds, extracted along with pigments from the skins of grapes during maceration. Hence much more present in red wines than in white (white wines are fermented juice; red wines are fermented juice and skins). Both tannins and pigments are classified as phenols because their structures include a 6-carbon benzene ring. Over time tannins can become bonded together, usually by oxygen molecules. Hence the name polyphenols, which have been linked to antioxidant properties of wine helping to prevent heart disease. Tannins are also extracted from seeds and from barrels. Cellulose is a combination of tannins with sugars.

Tannins can taste bitter, but primarily their effect in the mouth is a tactile sensation. You would recognize tannin most easily by imagining a cup of tea brewed with the tea bag for two minutes, compared to one steeped for ten minutes. Ten minutes gets you more tannins. They also contribute to ‘body’ in a wine. When green or immature, tannins are astringent. They got their name because of their usefulness bonding onto (and precipitating) proteins in the tanning of hides. When they bond onto the proteins in your saliva, they make your teeth and gums feel like each tooth just put on a new wool sweater. That’s why it is pleasant to eat a little cheese or salami with a glass of young red wine ~ the tannin in the wine can go after proteins in the meat or cheese instead of the ones in your cheeks.

Over time in the bottle (years), tannins will polymerize (bond together) with each other, with pigments, and with unfermentable sugars (e.g. 5-carbon sugars). The big molecules formed thusly will drop out of the wine. This will tend to remove astringency from red wines as they age. It will also contribute to sediment on the side of the bottle, which is a good reason to decant older red wines carefully. Sediment which gets into your glass won’t hurt anyone, but it tastes bitter, feels gritty, and makes the wine cloudy.

Tannins are most easily extracted from grape skins by alcohol in wines. Warm growing districts in California, which frequently get a percent or two more alcohol in wines than do the northern European districts, find tannin extraction commonplace, not a great achievement. This is a distinct contrast to northern European districts whose vintners employ multiple, often strenuous techniques for tannin extraction in order to give their wines some heft.


TERROIR ~ In a wine, the signature tastes and smells derived from the location whence the grapes came. It is not synonymous with quality. It is neither good nor bad. It may be pleasant or unpleasant, depending on the individual. It is an identifying characteristic.

The concept is that two identical grape vines grown in separate vineyards will produce grapes and wines that taste differently. Europeans tend to believe good wines are obligated to express the terroir from whence they came. Americans, by contrast, tend to believe winemakers should blend various terroirs together to achieve an outcome more pleasing than the component parts. To Europeans that activity is more akin to a carnival trick than it is to art.

Here’s a hypothetical depiction of the cultural distinction between connoisseurs in the US and in France:

Two vineyards are planted in Napa Valley. One is at 1,500 feet of elevation on the eastern side of the Valley above Oakville, where it gets direct rays from the sun in the late afternoon. The other is on the western side of the Valley, on a bench adjacent to Hwy 29, where the vineyard is shaded by the western mountains after 6:00 pm in August. Both vineyards have Cabernet Sauvignon and Syrah planted in them.

A French winemaker, selling in France, would blend the Cab Sauv and Syrah grapes together to produce two wines: A Hillside Cab-Syrah; and a Bench Cab-Syrah. A California winemaker, selling in America, would also produce two separate wines, but his would be a Napa Valley Cabernet Sauvignon (blending the hillside cab with the bench cab); and a Napa Valley Syrah (again, blending the hillside syrah with the bench syrah).


TIRAGE ~ French word refers to the manner in which sparkling wine bottles are stacked to age upon their lees , or spent yeast cells. The enzymes which escape when the dead yeast cells break open, or autolyze, add a little flavor, and a lot of smell to the wine. They also add a thicker, creamier texture. Hence the bubbles seem to come out of the wine more slowly, and the bubbles appear smaller in size. These changes do not happen right away while the bottles are lying en tirage. It is thought a minimum of two years on the lees is required to get a noticeable effect. Longer time confers a stronger result. Therefore, bottles with long tirage-aging will usually say ‘Late Disgorged’ on the label, or else carry a disgorgement date in the instance of vintage-dated sparkling wines. Some Champagne houses have even employed the procedure of disgorging small numbers (25 cases) of bottles only upon demand. Needless to say, these wines tend to be fairly expensive.


TOTAL ACID ~ Measurement of how many acid molecules are in a wine. Usually expressed as a percentage of volume. Red wines are lower than white wines. For reds, 0.55% to 0.60% would be a standard range; 0.45% would taste flat and mushy. For whites 0.65% would be more standard. German Rieslings routinely run between 0.80% and 0.85% ~ albeit often containing some residual sugar to modulate their severe acid bite.

Another way to discuss acid is in grams per liter. One g/L is equal to one/tenth of a percent. So a wine with a TA of 0.65% has six-and-a-half grams of acid per liter,

Acid is the backbone of wine, providing length and a crisp, refreshing quality to the flavor. Acid is the major reason a wine ages well. Tartaric acid usually makes up the lion’s share of a wine’s acid component, with malic and citric having smaller roles to play.


THREE TIERED DISTRBUTION SYSTEM ~ Arrangement dating from the end of Prohibition, intended to disenfranchise the Mob, which had become vertically integrated quite efficiently during The Great Experiment. In 1932 each state was granted the right to pass its own laws concerning alcohol sales. Most states opted to required alcohol produced out-of-state to go through a Three Tiered System in their state.

The idea is four legal entities with a transaction (or ‘tier’ where money changes hands and taxes are collected) between each one:

1. Producers (wineries or importers) sell to distributors (i.e. wholesalers) and pay a Federal Excise Tax;

2. Distributors then sell to retailers or restaurateurs and pay a state Excise Tax;

3. Finally retailers or restaurants sell to consumers and pay a Sales Tax.

The enabling legislation is called a Tied House Law. It prohibits ownership of more than one of the licenses above by the same legal entity. California does not have any Tied House Laws.

Starting in the 1970’s many states passed Small Winery Laws which allow their wineries to sell Direct To Consumers in-state.


ULTRA-RIPE ~ Since the mid-1990s it has become fashionable to make expensive red wines by leaving them on the vine an extra week or two after normal harvest indicators have been achieved. Instead of 23.5ºB, these grapes are often picked at 26º or 27º. There is usually some dehydration of the berries. For some years now it has been legal in California to add water to these fermentations. That used to be called “the Black Snake fix,” and talked about under one’s breath. Now it’s legal. It is necessary to add water in order to avoid stuck fermentations and/or very high levels of alcohol in the finished wines. The intense fruitiness of the wines easily stands up to the dilution. These are, incidentally, table wines. No one ever intends to make them into dessert wines by leaving residual sugar. The real attraction of these wines is their very high level of smooth, velvety tannins. The wines make quite a mouthful, but are not the least bit abrasive.


UMAMI ~ A fifth sensation registered by taste buds. In 1908 Japanese researcher Kikunae Ikeda isolated and identified one element of the umami taste – the amino acid glutamate. Today we see the application of that research as MSG (monosodium glutamate) indiscriminately put on food in many low-end Asian diners. Objection to treating this sensation as a basic taste diminished significantly in 2000 when Nirupa Chaudhari and co-workers at the University of Miami School of Medicine isolated and characterized a specific taste receptor for umami. Descriptions of the umami sensation are ‘savory, pungent,’ and ‘meaty.’ Glutamates help to pique other flavors. Glutamates are more common in aged cheeses, aged beef, and in bottle aged wines. Particularly in wines which have been aged sur lie – the dead yeast acting as a source for amino acids.


VERAISON ~ (pronounced ver AY shun) Point in ripening black grapes when the berries change color from green to black. It usually happens about six weeks before the grapes will be ready for harvest. Although it does happen in a day or two on an individual berry, it happens over three to ten days for individual clusters, and over about two weeks for entire vineyards. This discrepancy allows crews to remove clusters with a lot of unripe berries during veraison in order to bring the entire crop to ripeness more evenly, i.e. at about the same time. Removal of less ripe clusters by an experienced, well-motivated crew is relatively fast in California. Few other world wine regions enjoy this luxury because they lack the expertise and motivation in a readily available labor force.

Veraison (GI)


VERTICAL SHOOT POSITIONING (VSP) ~ Research begun in the 1970’s at the Agricultural Station in Geneva, NY spawned a number of experts, and a wide-range of grapevine trellising techniques which were a distinct departure from the common ‘California sprawl.’ Trellised vines in CA were generally grown in a cylindrical shape around a central cordon. The clusters were in the center hanging from shoots only a few nodes away from the cordon. The outside of the cylindrical shape had lots of leaves in the sun, but there were also lots of leaves inside the cylindrical shape that received very little sun because they were shaded by the outer leaves. For the plant, these shaded leaves were not productive, but they still required food and energy to maintain.

Vertical Shoot Positioning selects shoots which can be caught by a couple wires to form a vertical curtain above the cordon. All other shoots are removed. The result is an 8” thick wall of leaves, all of them in the sun. Originally recommended for cool growing districts where it was hard to ripen grapes, VSP techniques also produce wines with changed smell characteristics. Cabernet Sauvignon from Napa Valley is a good example. The California sprawl trellis gave Cabs with a pyrazine component to the nose. People who like that smell call it herbaceous; those who don’t call it vegetive. VSP trellising of Cab vines in Napa is more likely to yield cassis scented wines.


VINE AGE~ It takes three or four years after first being planted for grape vines to begin producing fruit. Then comes a period of increasing production as the roots expand to occupy the root zone. If the root zone is small, because of dense vine spacing or shallow top soil (as on a hillside), then this period of increasing production will be shorter (15 years instead of 40), and peak production will be lower. (See our blog post and tasting video which both address vine age).

Old Vine

Next comes a plateau period where vine production stays flat, followed by a period of declining production. It is impossible to assign ages to these changes in vine production with any precision because soil profile and vine cultivation appear to make such large differences. Logically grape variety and clone likely play roles as well. Nevertheless, older vines (those declining in production) are putting large amounts of flavoring material into smaller and smaller quantities of juice (hence wine). Concentrated flavor may not always be more pleasant to every taster. Intensity may emphasize a characteristic some people don’t enjoy. But concentrated flavor will always make the wines more complex. In the First Growth vineyards of Bordeaux’s Medoc district, grapes are usually not employed for an Estate’s primary label until vines are at least 25-years-old.

The phrase “Old Vines” is not governed by statute in California nor in the US. Consensus opinion amongst growers, winemakers, and journalists does seem to be 60 years or older. There are probably 5,000 acres of Zinfandel vines in California that are more than 80-years-old. There are such things as producing 110-year-old vines (Amador County’s Grandpere Vyd). Vines such as those usually bear only a small fraction of a ton per acre each year. It is hard to make up for this lack of production with a premium price ~ the premium would have to be a factor of 10 or 15 times higher. Hence bankers and accountants usually advocate for vine replacement when production starts to drop. Maintaining old vines for artistic purposes is a singular, multi-generational form of vinous stewardship.


VOLATILE ACIDITY  (VA) ~ The classic spoilage pathway for wines. When ethanol (the primary alcohol in wines) has limited access to oxygen, it forms small amounts of aldehydes. In small concentrations aldehydes smell like nuts, and are good additions to the complexity of the wine. With unlimited access to oxygen, however, and particularly in the presence of bacteria called acetobacter, the ethanol will form acetic acid, i.e. vinegar. Concentrations of less than 0.2 grams per liter of acetic acid give a wine complexity and seem to lift the fruitiness, making it more apparent. Concentrations above 1.5 g/l make the wine smell like salad dressing. Acetic acid also combines with ethanol to form ethyl acetate, which most consumers would recognize as nail polish remover. That’s a serious fault, which only extreme levels of body, fruit, tannin, and alcohol can overcome in a wine. This whole suite of issues is generically referred to as VA or volatility in wine.


WILD YEAST ~ An instructive generalization is to divide yeast for wine fermentation into two categories: (1) Saccharomyces cerevisiae, which are ellipsoid, i.e. oval shaped; and (2) apiculate yeasts, which form a point or apex. It is easy to separate yeast cells under a microscope using this shape distinction. Hence a pure strain culture of S. cerevisiae can be created. There are a bunch of apiculate yeasts, but they all share two features: (1) high ester production; and (2) low tolerance for alcohol. S. cerevisiae is just the opposite. That makes S. cerevisiae reliable. It will consistently ferment wines completely dry, and not introduce strong smells (from the esters). Apiculate yeasts give intensely scented wines, which can be impressive, but unless one has a lot of experience with the yeasts in question, one doesn’t know whether the strong smells will be pleasant or foul. It’s a risk. The further risk is that apiculate yeasts will get to 8% or 9% alcohol, then die, leaving unfermented sugar in the wine. That’s called a “stuck” fermentation.

During the ‘60s and ‘70s the standard procedure in California was to conduct fermentations by introducing pure strain S. cerevisiae cultures. The reason was so many CA vineyards were young. In Europe spreading skins back into vineyards after fermentation for hundreds of years had created huge yeast populations in those vineyards. The amount of new yeast which might blow into the vineyard during the year was miniscule compared to the yeast population already there. So a vintner felt pretty secure he could ferment with yeasts sticking to the bloom (waxy surface) on his grape skins, and get results very similar to previous years (or to results his father got). California vintners, with sparse populations of micro-flora in their vineyards were afraid their results would vary tremendously from year to year depending on whatever blew in. Europeans considered ‘wild yeast’ (or, more accurately ‘ambient yeast’) to be one of their greatest assets. Californians considered wild yeast to be overly risky.

The traditional technique in California was to inhibit the growth of wild yeast in a fermentation by inoculating at the crusher with potassium metabisulfite (which releases SO2). Then a culture of S. cerevisiae, which had been acclimatized to SO2, was added to the must (unfermented juice). Of course there are many permutations between the black and white of all pure strain culture vs. complete loosy goosy wild yeast fermentations. An example would be to let the yeast on the skins start a fermentation, and then introduce the pure strain culture to make sure the fermentation finishes successfully. Another technique is to use a cocktail of different yeasts. Another is to culture the yeast from a vineyard you like, and to selectively raise the percentage of S. cerevisiae in that.

Today the perception of wild yeast in California and in Europe is changing rapidly. Many California wineries have been doing larger and larger portions of their fermentations with wild yeast for twenty years. The stable micro-floras in their vineyards are increasing all the time. Their confidence knows fewer and fewer bounds. Meanwhile European vineyardists have had to choose between the asset of their wild yeast, and the benefit of modern mildicides which allow a crop to be harvested even in wet and miserable vintages. Mildicides not only eradicate molds and rots, but wipe out the yeasts in one’s vineyard as well. Those fermentations therefore require introduction of pure strain commercial yeast cultures.

This field of wine industry research has enormous potential. Think how important the role of micro-flora is to the dairy industry (cheeses, yogurts). Think as well how many yeast experiments a researcher can conduct each year compared to the number of vine growing experiments one can conduct in a lifetime.


YIELD ~ Volume of grapes produced per unit of vineyard. In America that would usually be tons per acre, although there is no reason it couldn’t as easily be gallons per acre. A ton of grapes produces about 155 to 185 gallons, or 65 to 75 cases. White wines can give up to 20% more gallons per ton than red wines do. Results depend on whether enzymes (such as pectin) are used, and how hard the skins are pressed. In Europe the most commonly cited ‘yield’ statistic is hectoliters per hectare.

Converting one set of stats to another is fraught with difficulties. One hectare is 2.54 acres. That is straight-forward, but an avoirdupois ton in America is 2,000 pounds. A metric tonne in Europe or Australia is 1000 kilograms, which equals 2,200 pounds. Hence 10 tonnes per hectare would be 22,000 lbs per hectare or 4.4 tonnes per acre (not 4 tons per acre). There are 100 liters in a hectoliter, and about 3.8 liters in a US gallon. Hence one ton per acre would be equivalent to something between 15 and 19 hectoliters per hectare. Average would be 17.5 hl/ha equal to one ton/ac.

Europeans tend to think less is always better: that reducing yield, by forcing the vines to struggle, gives more intense nose and more weight to the flavor. New World wine academicians tend to think a little stress is good, but that it is easy to go too far (as in drought years). California winegrowers generally feel healthy vines give the best quality wines. Furthermore a case can surely be made for the number of great vintages (evaluated by consensus of commentators) which were also very large vintages, both in Europe and California (e.g. 1987, 1997, 2005, 2012 in California).

Top quality Cabernets in Napa Valley are typically harvested at 3.5 tons per acre. Many appellations in France and Italy have yields limited by regulation. Most of those regulations specify yields under 50 hl/ha (3 tons per acre). Oregon Pinot Noirs seem to be harvested closer to 2 tons per acre. Of course there are always questions about how well regulations are enforced. If a French winery routinely sold some of their production under the table at a discount to a loyal contingent of customers, well … the customers and the winery would make out just fine ~ especially if it were a family tradition that had been going on for four or five generations, ever since the regulations went into effect. It’s not like Greeks fudging on their income taxes, is it?

A different problem is statistical accuracy. Any country uses a self-reporting system to arrive at acres under vines. Gallons of wine produced are a more believable figure, because those gallons are taxed. In 2007 at least one highly authoritative source reported 1,100,000 acres of grape vines in America, and 711,000,000 gallons of wine produced. That’s a yield of 3.8 tons per acre for all of America. That’s just not believable. Clearly lots of people around the country are claiming vineyard acres, who are not actually harvesting grapes nor producing wine.