System provides guidance on when, what to spray
By DAN WHEAT
WENATCHEE, Wash. -- When entomologist Vince Jones began researching leafrollers 10 years ago, apple growers and pest management consultants wanted to know what he was finding.
As had been done with other pests, Jones was building a model to predict the best timing for controls.
"With lots of insects it's fairly easy to do that," Jones said.
The problem was the leafroller has five to six stages in the immature phase of its life span, and the stages overlap. It was difficult to arrive at a model.
"It was hard to put it on paper and make sense of it, but we could look at it electronically more easily," Jones said at the Washington State University Tree Fruit Research and Extension Center .
With fellow entomologist and center director, Jay Brunner, Jones wrote a custom program for a spreadsheet that growers could use to plug in weather data and generate predictions.
In 2005, the Legislature funded the new WSU Agricultural Weather Network to replace and expand the Public Access Weather System. AgWeatherNet provides near real-time information about temperature, humidity, soil temperature and moisture from more than 130 stations.
Jones, Brunner and Gary Grove, plant pathologist and then AgWeatherNet director, developed the Decision Aid System for growers and launched it in 2007.
DAS uses current and historic weather data from AgWeatherNet in 10 insect and four disease models to help growers know when to combat pests and diseases. The models are based on cumulative heat units called degree days.
Growers can enter their own data or rely on daily automated weather updates from AgWeatherNet. Fed into the models, the information gives them pest and disease predictions and recommended treatments in accordance with WSU Integrated Pest Management.
There are two horticultural models. One is for storage scald of fruit. The other, added last July, is Professor Larry Schrader's sunburn model. It allows growers to enter temperature, sunlight, humidity, wind speed and apple variety to find out when fruit is most susceptible to sunburn. They can then decide whether to apply protectant or start overhead irrigation for evaporative cooling.
A Spanish-language version of DAS was added in December and another disease model, for cherry shothole, will be added soon, said Ute Chambers, another center entomologist who manages DAS.
Also new last year was the ability to get conditions and forecasts for any of the pest and disease models on smartphones, Jones said.
"You don't get the graphics, only current model conditions and management recommendations," he said.
Another new feature that will be added, Chambers said, is the Northwest Horticultural Council's database on the minimum level of pesticide residues acceptable on fruit in various foreign markets.
"Right now growers can get that information from the Northwest Hort Council but we want to make it easier," she said.
DAS had 533 users last year, representing a majority of the industry considering acreage and the number of orchards, Chambers said.
"We survey growers every couple of years and they estimate DAS saves them $75 an acre in improved timing, efficiencies and skipping nonessential sprays. It makes it simpler to do monitoring," Jones said.
Nick Stephens, president of Columbia IPM Inc., of East Wenatchee, and a tree fruit production consultant, uses DAS.
"It's the single greatest change in pest management technology since the degree-day model for codling moth," he said. "We used to do that by hand. DAS does it fast and in any format you want."
DAS is "hugely important," he said. Growers use it every day in season, he said, adding he worries most about how he would get his work done if funding disappears.
Federal and Washington Tree Fruit Research Commission grants have funded the program but are ending, Jones said. New grants are being sought but only pay for additions, not maintenance, he said.
While the innovation of DAS is making research useful for growers, Jones most enjoys the actual research.
Most of his work has been in biological control of pests. He's involved in a $4.5 million federal Specialty Crop Research Initiative looking at improving biological controls for pests in apples and pears in Washington and Oregon and walnuts in California.
"There are more types of insects than all other living things put together," Jones said. "Insects are amazing and survive in pretty harsh conditions. They adapt to every climate on earth except the deep ocean."
Hometown: San Diego, Calif.
Education: Bachelor's of science in biology, San Diego State University, 1978; master's degree in entomology, University of California-Riverside, 1982; doctorate in entomology, University of California-Riverside, 1983.
Occupation: Entomologist and behavioral ecology research professor, Washington State University Tree Fruit Research and Extension Center, Wenatchee, Wash.