Richard T. Nagaoka             
Viticultural Consultant
St. Helena, CA, in the heart of the Napa Valley

The following articles profile Rich Nagaoka's viticultural work:

"Networking in the Vineyard"

By Richard Paul Hinkle, Wines & Vines, February 1988.

There is no dearth of information in this business of vines and wines: it’s out there. There are technical journals, university short courses, and fence-post conventions. The free flow and sharing of viticultural and enological fact and fiction is winedom’s greatest strength.

The difficulty often lies in analyzing and interpreting that wealth of information, in sifting through occasionally conflicting evidence to get to the grain of truth tucked in amidst the chaff. That takes a certain kind of mind, a certain kind of training. What the Old West once called the "hired gun," we might translate into "vinous troubleshooter." Or, as Richard Nagaoka more mundanely refers to himself, viticultural consultant.

"This is a great business to be in, because there are no real secrets," said the quiet but intense Nagaoka, who grew up on a 40-acre vineyard in Lodi, Calif. "Everybody shares information, so the knowledge is out there for everybody to use. The question is, ‘How do we use that information?’ Too often we develop a theory and then try to justify it, instead of trying to find out why it really works. Or doesn’t work."

A U.C. Davis graduate, Nagaoka’s work experience covers both coastal and valley vineyard sites. he did wine and must analysis for Christian Brothers while running experiments on pruning, fertilizers, irrigation, and clonal selections. He spent 10 years with Gallo, directing research into insect, disease, and nutritional deficiency detection and the effects of cultural and environmental methods on wine grape quality. Before beginning his consulting practice, he returned to the Napa Valley as technical director for the Napa Valley Vineyard Company, where he directed cultural programs for 2,300 acres of vineyard, and designed and conducted research projects that led to the publication of scientific papers.

His consulting work, like Gaul of old, is divided into three parts: 1) wine quality strategies and crop protection; 2) contracted-for research (clonal and rootstock trials); and 3) feasibility studies for individuals and companies planning or acquiring new vineyards. "A lot of the wine quality work has to do with adjusting pruning levels, monitoring thinning, sod culture, and disease prevention," said Nagaoka. "These wine quality aspects are certainly the most interesting part of the job.

"Say you have a grower who’s delivering Chardonnay that’s acceptable for sparkling wine, but doesn’t quite come up to the winery’s flavor requirements for table wine. Sometimes it’s a pH problem, which we’re still seeing more often than we should. High pH fruit makes dull, flat, dead wines. The winery, of course, would prefer grapes that are in good condition, rather than have to resort to chemistry in the winery. Which means going back to the vineyard."

The answer, according to Nagaoka, is most often merely a matter of better light/canopy management. "In a sense, all we have to do is pay attention to our history. Most of the great wines have historically been produced on hillside locations, where you can’t develop a big canopy. Robert Pepi is a good example. Some of his growers were delivering Sauvignon Blanc grown in a shade regime, which yields wines with that domineering weedy, grassy character. Pepi, however, wanted a more melony, figgy, ripe character in his Sauvignon Blanc, so we had to change their training regimes to allow more light in, to expose the fruit more."

Irrigation management may provide another part of the answer to such questions, cutting off water to induce stress earlier than had previously been done. "Sometimes the growers were actually thinning too much," noted Nagaoka. "Balance, in the vineyard as in the wine, is still the ultimate key. The hard part lies in determining what that point is. Sometimes, too, we find overfertilization to be a cause of excess vigor, excess foliage, and sometimes we find a solution in encouraging a cover crop to waylay some of the water, to reduce the vigor. Rootstocks might even be the answer to some cases."

Though Nagaoka finds particular joy in conducting research projects, monies to fund them have dwindled during the last couple of years. "I guess it’s because of insurance liabilities, or something of that ilk," said Nagaoka. "It’s a lot of fun to work up the stats, to replicate and randomize, to find out exactly how the raw data can be translated into something a farmer can use. Last year, I ran a lot of evaluations for the chemical companies. Most of those were on fungicides for bunch rot and mildew, products similar to Bayleton. It appears that most of the problems people are having with Bayleton can be traced to sloppy spray coverage, which is why Bayleton is now recommending increased applications at lower rates-to improve the overall coverage."

For one winery, Nagaoka helped to isolated the finest Cabernet Sauvignon clones for a new planting the winery wanted done. For another, he ran an assessment on how cropping levels affected the color in Cabernet. "That was a good bit of research," he said with pride. "Once we found that the crop levels were a problem, we exaggerated them in one section to see how its color compared to a control plot. Sometimes, aggravating the existing condition is the best means of proving the culprit. To go back to the pH question we talked about earlier, you might use bird netting to increase the shade still further, which would really raise the pH and enhance the grassy character of a Sauvignon Blanc or Cabernet."

Nagaoka’s most recent project is an extensive, four-year research project funded by the late Winegrowers of California. "I want to track what the influence of devigorating rootstocks might be on the vine performance and wine quality of Cabernet Sauvignon," he explained. "Many vigorous and productive vineyards have been associated with negative wine quality. If devigorating rootstocks can impart some viticultural characteristics associated with high quality vineyards-by mimicking the effects often achieved by canopy modification, irrigation scheduling, and growth regulators-you ought to be able to improve wine quality by lowering production levels.

"Therefore, when I was with Napa Valley Vineyard Company, in 1982, we planted a trial block to Cabernet Sauvignon on 10 different rootstocks, a Richter, 5A Teleki, good old St. George, Castel 216-A, and Harmony. This is in a large vineyard, with heavy, river soils, land better suited to pasture than vineyard. The idea was and is to see if we could increase the wine quality by cutting vine vigor by means of various rootstocks."

Fruit form these vines has already been harvested, and Nagaoka has been monitoring brush weights at pruning, analyzing the juice, and evaluating the wine grown on each rootstock.

Nagaoka has been kept busiest these days by those requiring evaluations of vineyard acquisitions and potential new plantings. "It’s really important to have a good game plan when you’re getting into vineyard development. I’ve seen some guys out there tilling the land, and they’ve forgotten to order the rootstock! Everybody assumes that fumigation is necessary, but there are times when it could be counterproductive. You wouldn’t go in on a steep hillside and deep rip it and remove all the rocks. If you did, you’d lose tons of soil in the first winter rain."

Three big projects have cornered much of his time during the last year or so. "I was asked by the Whitbread/Antinori/Bollinger group to evaluate the vineyard they bought up in Foss Valley, a high valley parallel to the Napa Valley. Seagram wanted an independent evaluation of Rene di Rosa’s Winery Lake Vineyard, in the cool Carneros, and Buena Vista wanted help in matching the right varieties to the terrain in their huge new planting, also in the Carneros district. I’ve been busy."

Busy indeed. The $30 million Whitbread project (which signed on Dr. Richard Peterson as winemaker) involves an 1,100 acre parcel (170 acres of which are planted to Cabernet Sauvignon and Chardonnay) and winery development. "My study was pretty interesting, said Nagaoka. "Foss Valley is within the Napa Valley watershed, but is higher and parallel to the main valley. It has its own valley floor, with clays and heavy loam soils. It has east and west exposures on the hillsides, which makes it similar to the Napa Valley, but not equivalent.

"After collecting lots of information on temperatures and climate, we tried to determine how this area relates to the Napa Valley proper. There isn’t much precedent to work with, since there’s only one other vineyard near it. We think that bud break is generally later, that the mornings are warmer and the nights cooler, and that harvest will be earlier than the Napa Valley. There is a very positive inversion layer, which will minimize the need for frost protection, with as much as a 10 degree shift from the 1,450-foot Foss valley floor. and the 1,600 foot level. It’s really unique, which is what attracted Piero Antinori, who wants to make something different. His group had several opportunities to buy vineyards next to those with proven track records, but this is more attractive to someone with an inquisitive, questioning mind. They won’t be a big fish in a small pond here. They’ll be the only fish in the pond."

Nagaoka also enjoyed evaluating Winery Lake Vineyard for Seagram’s subsequent purchase. "Much of the work was in assaying soils, their depths, and locations for possible future plantings by Sterling," he observed. "The vineyard has surprisingly good depth and uniformity for the Carneros [notorious for thin, shallow soils]. It’s in an interesting area of sedimentary soils that were lifted up and redeposited eons ago. And Rene di Rosa’s an interesting guy to interview and work with."

A stone’s throw away, Nagaoka has been working closely with Buena Vista on their extensive new planting in the lower Carneros. "I have been working with viticulturist Anna Muller-Racke on their vineyard practices, soil chemistries, and nutritional work before, but this new planting, of nearly 600 acres, is most exciting. I feel like an architect, trying to match each variety to its best location.

"It’s an accepted rule that Cabernet Sauvignon will not grow here, that it’s too cool."

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"Phylloxera – Special Investigative Report"

Wine Spectator, August 31, 1992.

Phylloxera, Daktulosphaira vitioliae, is a formidable pest. Its life cycle in California (the insect’s life cycle is markedly different in Europe) remains a mystery even to experts such as Davis entomologist Granett, who has been studying it for more than 10 years. Because it attacks vines deep in the root system, there are no effective chemicals that can be used against it. And even if there were chemicals, phylloxera’s prodigious reproduction rate could overwhelm their effects. One female can reproduce 200 offspring, with a generational cycle of 30 days. That amounts to a billion bugs within a year. They cover the roots in n orange and yellow mass. Their feeding causes roots to swell and galls to form below which the roots die.

Granett still doesn’t know whether the new biotype could have been carried into the state or whether it was created by mutation. Unfortunately, while rootstocks transported into California were routinely quarantined for disease and other pests, they were never quarantined for phylloxera. Even looking at the reproduction of the insect is perplexing: All California phylloxera are females, and they reproduce at will. But that means mutations shouldn’t happen because the gene pool remains constant. To top it off, phylloxera has no known natural enemies.

Phylloxera’s method of locomotion is also a mystery. Many blame drought-weakened vineyards for allowing the pest to proliferate. Others say the flood that hit Napa Valley in 1986 spread phylloxera throughout the valley floor. Many growers in the valley also blame independent vineyard management companies for inadvertently transporting the insect. It may travel in clumps of mud that cling to farm equipment if the equipment isn’t cleaned between jobs. It may crawl from vine to vine, or it may be primarily wind-borne.

While questions of how it spreads are important for scientists, the vital question for many growers and vintners now is how fast it is spreading. There is always some replanting going on for a variety of reasons in the wine country. Most grafted vineyards have to be replaced after 25 or 30 years because of declining productivity. Consumer tastes can also dictate plantings. Then there’s a whole host of biological infestations that doom vineyards. At any given time, 5 percent of the vineyards in Napa are being replanted.

"If you plant 18,000 acres between 1990 and 2000, that’s business as usual," says Napa Valley grower Andy Beckstoffer. "If it’s done in three years, that’s a serious problem. We replant vines around here all the time."

Phylloxera is prompting many winemakers to repeat the mantra that the vineyards of California will be replanted for the better. They may be right. While the technology of California winemaking has reshaped the world, its track record in the vineyards has lagged. Standard vineyard practice has been to plant rows 12 feet apart and space vines every 8 feet in each row.

In the replantings, spacing of 5 feet between vines is common and even closer spacing is being tried. New trellising techniques are being used to allow more light and air to reach the vines-elements that help grapes ripen more evenly and flavorfully. Vine densities would double to 900 vines per acre with 8 feet-by-6 feet spacing. At the Robert Mondavi Winery, vineyard manager Freese is pushing ahead with densities of up to 2,500 vines per acre, and is experimenting with a pattern that will allow 4,000 vines to the acre. These densities replicate those in France, where vines are grown much more closely to the ground. Currently in California, trellising can reach 6 to 8 feet in height, but at Mondavi, the vines are being planted to grow to higher than 4 feet.

So far, grape growers are replying on three or four different types of phylloxera-resistant rootstocks to replace the failed AxR #1. According to Andy Walker, a viticulturist heading up rootstock research at UC Davis, Californians of yesteryear may have been onto something with St. George; it is especially drought resistant. Two of the more popular rootstocks being used growers today, 5c and 3309, may be less desirable in the long run because they were propagated for a wetter and cooler northern European climate.

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"Vintners Look to the Grape to Bring Shine to the Bottle"

(citation to follow)

No longer bound by the dictates of Europe-inspired viticulture, Napa Valley grape growers are altering the face of the nations famous wine country.

In the past decade, most vintners have discovered that their best wines ware made in the vineyards, not just in cellars stacked with stainless steel tanks and oak barrels.

This realization has led them to other discoveries, like better ways to bring grapes to harvest, to eventual end product – an exceptional bottle of wine.

Viticultural breakthroughs at universities and government-funded experimental stations have prompted grape growers to plant heartier clones and to look at the growing cycle with new understanding.

Denser spacing in the vineyards, new trellising methods and the steady march toward elimination of pesticides and herbicides are boding well for an even healthier wine industry today.

Accelerating the marked changes in valley viticulture is the insatiable root louse, phylloxera, on track to wipe out two-thirds of the valley’s vines, once thought to be resistant to the tiny insect.

"Phylloxera is initiating changes sooner than might have been planned, "says Richard Nagaoka, a 28-year veteran of California viticulture. " I think we’ll see a majority of replanting in the valley occur within this decade rather than be spread over a normal three-decade replanting cycle.

"I think historians will look back at this period as a time when there was a definite change in the appearance of our vineyards."

Nagaoka says growers have become concerned about "the environment of the (grape) cluster. There’s a move to carefully control the amount of sunlight each cluster gets."

This is taking the form of methodical "shoot positioning." Nagaoka advises, as growers employ a means of training vines known as "vertical trellising."

Some growers believe they get the best results from vines by diving the canes into two rows instead of one. It can be accomplished with an "open lyre," or harp-shaped trellis.

There’s also another trellising method employed by growers called Geneva double curtain. It also splits a single row of vines into two canopies. But here the shoots hang upside down.

Getting better air and sunlight exposure "results in better color and fruit composition," the well-known vineyard consultant allows.

Nagaoka points to new plantings that match soil composition to rootstock and varietal type.

"We are being more site specific with our vines now," he said. "We are looking at the potential of the vigor of the soil and matching it to the appropriate rootstock and varietal."

There are hundreds of grape rootstocks, he continues, "but few are commercially available in America. I think that will change in this decade and we’ll learn more about their performance in California (vineyards)."

For the moment, growers must choose from among a half dozen of the most popular rootstocks for their replanting programs.

Nagaoka sees few new properties being developed for vineyard. Most of the current activity is in replanting.

One of the most common trends is planting vines closer together. This denser spacing results in lower crop yields per vine, to be sure. But it also accounts for more tonnage per acre.

For example, Nagaoka helped Delta Viader develop a vineyard that runs up and down a steep slope overlooking Bell Canyon reservoir. With this planting method-as opposed to trellising along contours-the viticulturist was able to retain the natural top soil.

Here, spacing of the vines is six-by-four feet, which allows for 1,815 vines per acre. That compares to an average vineyard of the ‘70s with eight-by-twelve-foot spacing, or 500 vines per acre. Even denser spacing in some areas allows for as many as 2,500 vines per acre, Nagaoka says.

"Some growers may disagree, but I think most feel the better wines are produced from vineyards where the yields are lower," he adds.

Organic farming is playing an increasingly important part in valley viticulture as well, the vineyard consultant adds. "We are seeing less and less application of pesticides and fertilizer, for an overall reduced chemical input.

"Nitrogen-producing cover crops, like vetch, peas and fava beans, are being planted between rows. The historic purpose of these crops was to reduce erosion, but now it’s to enrich the soil."

Nagaoka says growers are replanting the most profitable varietals. "If you have a good cabernet sauvignon vineyard, you’re replanting it.

"Merlot is being widely planted now as well and may soon overtake cabernet sauvignon."

He also notes the less popular varietals will not be replanted here. However, several growers-looking to the future-are replanting their vineyards with varietals commonly associated with France’s Rhone region and several grape growing districts of Italy.

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"Vintners Take the Pledge"

By Richard Figiel, Sierra [Magazine], November/December 1994, pp. 51 ff.

The speaker stood at the front of a crowded hall in Davis, California. "My name is Rich," he began, "and I’ve been chemically dependent…" The audience burst into laughter, drowning out his punch line: "…mostly on organophosphates."

Richard Nagaoka, a high-powered Napa Valley vineyard consultant, was addressing a group of grape farmers and winemakers at a University of California Extension seminar titled "Going Organic." He went on to describe his running battles with the grape leafhopper, a bug smaller than a grain of rice that has become a major pest in California vineyards.

Nagaoka had found himself in a vicious cycle: as leafhoppers kept adapting and building up resistance to each petroleum-derived, organophosphate insecticide used to control them, he would switch to a new formulation. Even after spraying the leafhoppers repeatedly through the season, huge populations would still confront him. Unable to control them with chemicals, he says, he finally turned to an organic strategy "by default."

The transition wasn’t easy. Withdrawal from insecticides meant several years of agonizing crop losses until the leafhoppers’ natural predators-whose numbers had been decimated by the barrage of pesticides-could get re-established in the vineyards.

Nagaoka was hardly alone on that treadmill. Many farmers continue to walk it, whether they grow grapes or grains or green beans. Cornell University entomologist David Pimentel says pesticide use has increased 33-fold on U.S. farms since 1945, when synthetic agrochemicals were introduced on a mass scale. Yet over the same period, losses to pests have increased, from about 31 percent to 37 percent of crop totals. Produce, of course, is not the only thing at risk. Despite their increasing ineffectiveness on adaptive pests, agricultural chemicals take a serious toll on human health. According to the World Health Organization, there are a million nonlethal poisonings from pesticides each year among agricultural workers and consumers, and about 20,000 deaths.

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©1999 by The Grape Doctor, Richard T. Nagaoka, Viticultural Consultant
1171 Edwards Street, St. Helena, CA, 94574-1208, USA -- --