Glassy-winged sharpshooters grab all the headlines, but local vineyard owners face yet another–perhaps even more insidious–threat
By John Nagiecki
MILK CARTONS stand like small tombstones in Bill Lerner’s Santa Rosa vineyard. From within the open cartons grow young chardonnay vines, whose thin crooked trunks rely on rebar stakes for support. To the untrained eye, the field looks like any other new vineyard in the county, with its small plants and forest of tall posts strung with trellis wire and irrigation tubing. But Lerner says his vines are diseased. He complains that, since he planted the vineyard in 1999, he has had to rip dead vines out and that others have grown spindly and weak. He has recently had to prune some of his vines back, giving them another chance to develop needed girth.
Lerner cuts open two vines to show why they are growing poorly. Tiny black specks dot the inner wood of the first vine. The second has a darkened core. Lerner says it is black goo.
Black goo is the nickname given to a type of vine ailment known as young-vine decline. It is associated with a group of fungi that live in the woody part of the plant. The black or brown gooey substance produced in the wood is the vine’s response to the pathogens’ injurious effects. But goo is not the only product of this disease. It has generated about as much, if not more, acrimony within the wine industry as it has dead wood.
Young-vine decline, according to some, is an insidious problem, threatening to cripple the region’s $2 billion grape-growing industry. Though it is not a new problem, it has become more prevalent recently because some nurseries allegedly have been selling diseased vines to unsuspecting growers. Others claim that young-vine decline is a nonissue, which affects only a tiny fraction of the vineyards in the county. They say it exists mainly in fields managed by growers who don’t know how to properly care for their vines. This latter group asserts that the disease continues to attract attention because small but outspoken vineyard owners are trying to indict nurseries for losses that are actually owing to their own mistakes.
Young-vine decline was among the topics discussed at last month’s meeting of the Sonoma Valley Vintners & Growers Alliance. The event featured scientific experts, vineyard consultants, and nursery representatives who offered their views and responded to questions regarding the problem.
The controversy surrounding the disease centers, in part, on whether the fungi–one of which goes by the name Phaeoacrimonium–will necessarily harm a young plant, or whether poor vineyard management is to blame.
According to Dr. Douglas Gubler, head of the plant pathology department at the University of California at Davis, “Stress is the key to this whole big picture.” Gubler, whose department has been studying the disease, defines stress in terms of restrictions on root system growth, including poor planting, water deficits, or even the production of fruit on the vines too early in their life, all of which can trigger a pathogenic response.
But Michael Porter, a viticultural consultant based in Forestville, disagrees. “Everything is called stress,” he says. The problem as Porter sees it is not whether a plant is mistreated, but whether it’s carrying a pathogen. He invokes the findings of international researchers who view stress not as a cause but as a catalyst of an infected vine’s decline. “The fact is,” he says, “that an infected vine is much more sensitive to stress. If it were not infected, it would be much more tolerant of stress.”
Along with the feud over the role of stress and infection in a young vine’s decline is a divide regarding the extent of the disease.
Gubler says that the whole problem has been grossly exaggerated. “This thing is being trumpeted as a huge problem,” he says. “For the guys who have the problem, it’s a problem. But industrywide it’s not.”
He adds that young-vine decline is confined largely to Sonoma County, estimating that no more than 1 percent of the acreage is affected. “Where we see this problem occurring most frequently,” says Gubler, “is in vineyards, usually small vineyards . . . that are not owned by traditional vineyardists that have been growing grapes for years and years.”
Porter thinks that Sonoma County may indeed have seen more than its share of young-vine decline. He first came across the problem at a Russian River Valley vineyard in the summer of 1991. He describes it as a vineyard “with wonderful soil and very experienced management.” Since 1991, he indicates, more than half of the vineyard’s vines have been replanted.
But Porter also sees the problem reaching beyond the county’s borders. “I’ve got lots of clients in Napa Valley who have a huge problem,” he says, adding that the problem also exists in South Africa, Australia, Chile, France, Italy, and Portugal.
He emphasizes that the fungi-induced disease is likely far more widespread locally than officially reported because vineyard managers often don’t know they have the problem and are not curious. “They’ll pull out vines that are sick and replant,” he says, “but don’t send the sick vines in for testing. They just throw them away and say, ‘Ah, must have been gophers.’ ”
Porter also believes that some managers are reluctant to say that their vineyards are diseased because they don’t want to scare the bank.
Gubler strongly disagrees with Porter on these issues. “I can’t imagine why somebody wouldn’t want to know that they’ve got a problem,” he says. “That doesn’t make sense.”
Nevertheless, Gubler agrees that lenders are part of the picture. The difference is that he sees bank loans stressing out growers who, in turn, stress out their vines. “Growers are finding themselves in a situation to produce a crop on those vines very early to start repaying the bank, and the vines can’t take it. So there’s predisposition stress.”
Again, Porter disagrees. He blames sloppy propagation practices at some nurseries as the reason young vines are becoming infected by pathogens. “It’s really your source that’s most important,” he says.
Gubler agrees that nurseries may be selling vines that harbor fungi. “There’s no doubt that some of the wood coming out of nurseries have these fungi in them,” he says. “But just because they have fungi in them doesn’t make it bad wood.”
WHATEVER the criteria, separating the good wood from the bad is something some growers worry more about these days. Some now hire experts to help them identify and plant good vines. James A. Stamp, a plant biologist and viticulture consultant based in Sebastopol, assists growers from coast to coast with young-vine decline problems. “Bad vines are shipped everywhere,” he says, “and you see signs of poor vineyard performance in many different places.”
Stamp, who completed a post-doc fellowship at UC Davis and has since started two nurseries, helps prevent weak vines from getting into a grower’s field by carefully inspecting a nursery’s practices in advance of delivery. He also provides the nursery with specific procedures and protocols to follow in the preparation of his clients’ grafted vines, and he checks on their condition until planting time.
For other clients who have already ordered vines, he ensures that what gets delivered is, in fact, worthy of being planted.
“We’ve rejected a lot of vines,” says Stamp. “I’ve rejected whole batches of 50,000 or 100,000 vines in particular cases.” He indicates that in any given shipment about 20 percent of the vines are sent back. In very good cases, only 5 percent will be bad. Overall, he estimates he’s rejected about 40 percent of the vines shipped to his clients.
In a recent issue of Wine Business Monthly, Stamp states that, until recently, the surge in demand for new vines had contributed to a corresponding drop in nursery-stock quality. The thirst for new vines has been so intense, he observes, that many nurseries had sold their entire crop two years prior to delivery. Stamp concludes that “vine quality is perhaps one of the biggest casualties of the recent California vineyard expansion.”
In the future, Stamp expects California grape prices to fall, which should lead to more competition among nurseries, along with a corresponding drop in prices and improved quality. In the meantime, those who have weak vines are either replanting parts of their fields or waiting to see whether their plants will regain some vitality.
MITCH PATIN manages 750 acres of vineyard in northern Sonoma County. Patin, who has been in the business since 1977, has been surprised by the failure of some of his young vines. “We never had this kind of problem 10 years ago as we have now,” he says. Over the last five years, Patin has had to remove 60 acres of vines. He recently pulled out an entire 12-acre block. Overall, he estimates it cost approximately $30,000 to $40,000 per acre in lost production and redevelopment expenses.
Patin is reluctant to point any fingers; he just wants the problem solved.
Bill Lerner says he would like his money back for vines he bought in 1999 from Sunridge Nursery in Bakersfield. Though the nursery has offered to replace all of his vines, Lerner has refused, claiming the replacements would not be healthy. Visiting the facility in December of 1999, he had the opportunity to cut open some nursery vines. “I wanted clean vines,” says Lerner, who claims he saw the same discoloration there that he saw in the vines delivered to his field.
Glen Stoller, founder of Sunridge Nurseries, says his plants are not diseased. He indicates that Sunridge, a family-owned nursery that’s been in business since 1977, sells up to 10 million vines a year. “How long do you think we’d stay in business,” he says, “if we were shipping diseased plants?”
Stoller says that “the same lot of plants that we shipped [to Lerner], we shipped to other growers. And we went and checked all those other vines, and everything was doing beautifully.” He adds that a company representative and consultant looked at Lerner’s vineyard. They determined that Lerner had waited too long to remove the mounds of dirt that had been piled around his vines, something that is initially required to protect the fledgling plants.
Stoller also says that Lerner planted in the latter part of June, which was too late in the season. “This is dormant material,” says Stoller, “he should have planted in February or March.”
He also cites Lerner’s inexperience, noting that “this is his first attempt at a vineyard.”
FROM WHERE he stands, Lerner believes Sunridge sold him stock that no one else wanted. He complains that the plants he received were sprouting, which is not what a dormant vine should be doing. “I spoke to one expert that’s farmed here for many years,” says Lerner. “I showed him the shooting, and he shook his head and said that shouldn’t be.”
Lerner explains that the tender shoots were unavoidably lost during the planting process, causing the vines to channel their limited energy stores into yet another set of new shoots. Nevertheless, he believes that had the vines not harbored a fungus, they could have withstood the stress imposed by the lost shoots.
Though frustrated, Lerner says he’s not going to give up. Last year, he decided to remove and replant the field of 5,600 pinot noir plants from Sunridge, using stock that he bought from another nursery. He would like to replace all of his chardonnay vines as well, but is constrained by the cost and the inability to find what he considers acceptable vines.
Research efforts around the world are under way to solve the young-vine decline problem, focusing both on the pathogenic agents and on their means of transmission. For example, UC Davis researchers recently discovered a new latent virus that is responsible for the disease. Other research is focusing on chemical treatments that can be applied to vines during propagation.
Porter is optimistic that international efforts will find a way out of the problem. “We should be able to get it out of the plants before they go into the ground,” he says.
Gubler states that considerable progress in understanding the disease has been made in the last few years. He also believes that research is under way to find out what triggers the fungi to become pathogenic in the plant.
Stamp believes that in the wine industry’s hierarchy of concerns, young-vine decline has already fallen off the radar. He believes that it has been displaced, in part, by concerns over Pierce’s disease transmitted by the glassy-winged sharpshooter. Nevertheless, writing in Wine Business Monthly, he still advises everyone to “take a close look at your new vines.”
John Nagiecki is co-author of ‘California’s Wine Country’ (Falcon Press, 2001).
From the March 29-April 4, 2001 issue of the Northern California Bohemian.