Bold, fruity, with a hint of RoundUp...

Some vineyard managers are trying to kick the RoundUp habit, others see it as a bottom-line issue|

It used to be the postcard view of the Sonoma Valley: rows of trellised vines flowing over the landscape, the manicured and weed-free earth between them.

“We don’t want that,” said vineyard manager David Cook. “We’re OK with weeds.” The fourth-generation farmer – and current Sonoma City Council member – is trying to wean his clients off using RoundUp, the weed-killer coming under increasing scrutiny because of health concerns.

“We want to have the ladybugs, we want to have the spiders, the rattlesnakes – we want those in the vineyard, this is all good stuff to have,” said Cook. “And part of the balance is not nuking everything.”

A spate of recent media reports on the prevalence of glyphosate – the active ingredient in the weed-killer RoundUp, and one associated with increased cancer risk – is causing concern among Sonoma’s wine lovers. According to a recent headline-grabbing lab test – in which wine samples were analyzed for glyphosate levels – all 10 of the submitted wines from Napa, Sonoma and Mendocino counties showed positive results for the herbicide.

The use of RoundUp is widespread and has over the years become deeply engrained in the way grape growers do their business, say local grape farmers, but the alternatives may bring risks of their own.

“RoundUp has been used in vineyards now for 30 years,” said Mike Benziger, former owner of the Glen Ellen winery that still bears his family name. “It’s incredibly effective, it’s relatively safe, and it’s cost effective too.”

Though Benziger is doubtless concerned about the health risks of glyphosate – most of the vineyards he built up since 2000 when he was still owner of Benziger Winery are either biodynamic or organic or both, which prohibit chemical additives – he points out that with increasingly sophisticated testing methods, even the tiniest amounts of chemicals can be detected. “You’d have to drink, I don’t know, hundreds of bottles of wine to reach the levels which would be considered over the limit.”

The test results, from St. Louis commercial lab Microbe Inotech, have been promoted by an organization with the unimpeachable name Moms Across America, and received air time on several major news outlets in the Bay Area and beyond. All of the wines showed traces of glyphosate; four of the wines had glyphosate in such concentration that testing could not determine the amounts without dilution. Overall, the glyphosate count registered from 0.66 parts per billion to 18.74 parts per billion.

The published Microbe Inotech report does not identify the wines that were tested, aside from saying they were from the North Coast area that includes Sonoma County. Supposedly at least one of the wines was identified as organic, but the lack of supporting information makes it difficult to evaluate the wines’ appellation, label, varietal or anything else.

“The brands are welcome to test themselves and reveal the info themselves,” said Zen Honeycutt, of Moms Across America. “Frankly, the brands are not the issue. The real issue is the widespread contamination of glyphosate based herbicides in consumer products.”

Former Monsanto employee, Dr. Bruce Hemming, now works for Microbe Inotech, the lab that produced the wine-glyphosate research results. He said the test was conducted at the request of a client.

“I worked for Monsanto for 10 years in biotechnology when they were first starting it up,” said Hemming. “I’m not a disgruntled employee by any means, but I do see that there are significant data (studies) that need to be done.”

Monsanto is the company that manufactures and sells RoundUp, in a number of different formulas, for home and commercial use.

Monsanto is experiencing a wave of negative publicity around this report and others, including a 2015 determination by the World Health Organization (WHO) that glyphosate a probable carcinogen. In January, Monsanto filed suit in California seeking to prevent glyphosate from being added to the state’s list of known carcinogens.

However, this month, Reuters reported that a joint WHO/FAO (the U.N.’s Food and Agriculture Organization) said glyphosate is “unlikely to pose a carcinogenic risk to humans” exposed to it through food, apparently contradicting its earlier finding. The research, and the debate, continues.

Sonoma vineyard manager Phil Coturri says he hasn’t used RoundUp since 1977.

“You can’t constantly use a product and think that it’s not going to have an effect,” said Coturri, who was recognized by the Golden Gate Salmon Association earlier this year for his environmentally-sound viticulture. “Glyphosate is something that’s made to kill.”

Among the other methods of weed control available to farmers are disking the soil and the use of “weed-whackers,” both reliant on experienced laborers and machines. Both of these methods also require gasoline motors to operate. “We feel like we’re doing the right thing, but if you’ve got four weed-whackers going through the vineyard, they’re all causing greenhouse gasses,” said Cook. “I have some clients who tell me they would rather use RoundUp than weed-whackers, because of the carbon footprint.”

It’s one thing to consider any toxic effect on consumers drinking wine with residual glyphosate, it’s another to weigh the cumulative effects of the compound in the soil – and the effect on the vineyard workers who apply the stuff. Last week a story in the “adversarial journalism” website reported on two agricultural workers who used RoundUp on a persistent basis. Both, according to the site, developed non-Hodgkin’s lymphoma, and are blaming and suing Monsanto.

“The food that we eat should be sacred,” said Coturri. ”The overuse of any chemical, especially made by Monsanto, I don’t trust.”

Monsanto, not surprisingly, is aggressive in combatting these reports. The Index-Tribune received a statement from Monsanto, reading “Glyphosate is one of the most extensively studied agricultural products on the market and glyphosate-based herbicides have a 40-year history of safe use. Regulatory authorities have determined that glyphosate can be used without unreasonable risk to human health or the environment.”

In commercial use, glyphosate is a regulated product – and a widespread one. According to figures from the California Department of Pesticide Regulation, in 2014 almost 77,000 pounds of glyphosate were applied on 48,137 acres of wine grapes in Sonoma County.

But there’s also private use – the spray-bottle the home landscaper or gardener uses. “Don’t forget you can buy it and use it all day long in your backyard,” said Benziger.

All agree that it’s not just a question of conviction, but economy: given enough available skilled labor (also in short supply, according to our sources), and financial incentive, it is certainly possible to produce wine that is RoundUp-free. But the tolerance of the marketplace to support fully organic, pesticide-free wine at the price point it would require will be the ultimate judge.

“I’d rather produce three tons an acre of fruit that goes into a $100 bottle of wine than six tons an acre that goes into a bottle I don’t want to drink,” said Coturri.

In the end, then, it all comes down to the consumer: What’s in your wine cellar?

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