Department of Horticulture and Landscape Architecture

Viticulture & Enology

Undergraduate Research

Iraq War Vet Comes Home to Wine Country

by Brian Clark
CAHNRS Marketing and News Services

“The U.S. Army is a 200-plus-year-old organization,” said WSU viticulture and enology student Andrew Schultz. “They know something about leadership and teamwork. That’s why I served.”

Andrew Schultz
Army veteran Andrew Schultz recently completed a grapevine leafroll disease inventory for Kilpsun Vineyards. Photo by Naidu Rayapati.
Typical symptoms of grapevine leafroll disease include reddish, fall-colored leaves.
Typical symptoms of grapevine leafroll disease in red varietals include reddish, fall-colored leaves. Photo by Naidu Rayapati.
Naidu Rayapati, WSU plant pathologist
WSU plant pathologist Naidu Rayapati. Photo by Dennis Brown.

The former radar operations sergeant served in the Army for four years, including 16 months in Iraq, before returning to civilian life, his beloved Pacific Northwest and the continuation of his college education.

“I originally wanted to be a graphic designer,” Schultz said. “But at some point I realized I didn’t want to sit in an office all day. So I joined the Army, saw the world, and decided to study the science of wine at WSU.”

Now the undergraduate is working with WSU plant pathologist Naidu Rayapati to take stock of grapevine leafroll disease in the region's vineyards. He just completed an inventory of leafroll disease for Klipsun Vineyards on Red Mountain. In 2004, Wine & Spirits magazine named Klipsun one of 25 best vineyards in the world. The vineyard’s grapes are widely sought after by the region’s top winemakers.

Grapevine leafroll disease can cause a marked decline in grapevine vigor, grape quality and productivity, according to Rayapati. The disease can reduce yields as much as 50 percent or even more, depending on the severity of infection. A few years ago, it was estimated that nearly 10 percent of Washington’s vineyards have grapevine leafroll disease. Anecdotal evidence suggests that the disease is more wide spread than previously thought, raising alarm among industry stakeholders. Grapevine leafroll disease accounts for about 60 percent of the production losses of grapes worldwide, Rayapati said.

“It’s nothing anybody had control over," said Klipsun’s vineyard manager, Julia Kock. "At the time these plants went in, in the 1980s, there was no effective screening process for these viruses. People believed they were planting clean material. Now we need to understand the extent and significance of the disease. The first thing to do is to take stock with a visual evaluation and to conduct some lab analyses. Then we must decide if this disease is detrimental to our site. We are pleased to be able to turn to WSU research and Naidu’s program for help.” Kock is a 2004 graduate of WSU’s viticulture and enology program.

Klipsun Vineyards and Rayapati partnered to inventory diseased plants in the vineyard. Together, they hired Schultz to conduct the inventory. Using visual inspection of red varieties, which show symptoms via fall-colored and spotted leaves, he created a spreadsheet, indicating diseased plants row by row. This fall and winter, he’ll enter the spreadsheet data into a GPS system in order to better visualize the spatial distribution of infected plants.

But already a pattern is clear, Schultz said. “When they’re planted side by side, you can see the spread of the virus from the old blocks into the newer ones.”

While recent research in California has confirmed that the grape mealybug spreads the virus disease, humans are probably the primary means of spread through the propagation of infected vegetative cuttings.

“Knowing what is out there is part of dealing with the problem,” said Rayapati. “This information is critical for designing appropriate strategies to tackle virus diseases in our vineyards.” The best insurance against the disease is to plant material that is certified to be virus free, Rayapati said.

Schultz will also work with Rayapati to test plant samples for leafroll viruses using PCR and ELISA procedures. Such lab-based analytical methods are the only ways to know for sure that a plant is infected. The Northwest Grape Foundation Service, which provides plant material to the industry, uses PCR and ELISA and other techniques to insure vineyard stock is virus-free.

“Connecting industry professionals with WSU students is one of the ways we make sure our graduates have the practical experience they need to be leaders in the industry,” said Rayapati.

To illustrate the point, Rayapati pointed to Landon Keirsey, an undergraduate researcher working with enologist Jim Harbertson.

“Recently, Landon pressed some grapes from infected and non-infected vines,” Rayapati said. Keirsey analyzed the juice and found that juice from infected plants was lower in sugar content than that from non-infected plants. “Landon said to me, ‘Hey! I remember you talking about this in class last year.’ It really connects the classroom with the real world.

“It’s very important for students to have field experience in order to understand how to maintain healthy vineyards for producing quality grapes. And this means working with not only scientists but growers such as Julia as well,” Rayapati said.

“The same is true for wine quality,” agreed enologist Harbertson. “We don’t know for sure what effects leafroll virus has on wine quality. When you have less sugar and more acid, there is some impact, but is it noticeable outside the lab? We’d like to investigate this more to determine if the impacts on color, tannins, acidity and ethanol are significant.”

Both Schultz and Keirsey have received undergraduate research grants that will enable them to continue their work. Keirsey continues his research on co-fermentation while Rayapati said that Schultz will investigate virus-infection rates in other vineyards.

“I love wine, I love being outdoors, I love living in the country,” said Schultz. “And this is great. I wanted to be part of a team, to have a hand in putting something together, in getting the job done. And that’s just what we’re doing.”

This article originally appeared in the Voice of the Vine newsletter.

More information

Both Andrew Schultz and Landon Keirsey, the two WSU undergraduate researchers mentioned in this article, have grants to fund their work. Learn more about undergraduate research projects in the College of Agricultural, Human, and Natural Research Sciences by watching this short video:

Learn more about Naidu Rayapati's research by visiting

Learn more about clean plant material from the Northwest Grape Foundation Service Web site:

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