Oregon’s battle with gypsy moths enters detection phase

By Oregon Department of Agriculture,

About 15,000 gypsy moth traps will soon be placed statewide. By the end of the month, roughly 15,000 bright orange and green tent-like cardboard traps will be placed in trees and shrubs throughout Oregon as state officials go about the annual process of looking for gypsy moths over the summer months. Combined with a number of other traps for insect pests ranging from Japanese beetle and a variety of exotic fruit moths to Asian longhorned beetle and emerald ash borer- two insect pests yet to be found in the state- the Oregon Department of Agriculture should learn which bad bugs are problems this year and where they exist.

“Our approach is early detection and rapid response,” says Helmuth Rogg, supervisor of ODA’s Insect Pest Prevention and Management Program. “Placing traps statewide will help us detect any small population of gypsy moths and other unwanted insect pests that can be eradicated before they spread.”

Last year’s traps yielded 12 gypsy moths, seven of which were found in an area of southeast Eugene where moths were trapped in 2007. That led to a 626-acre eradication project which began in late April and is just finishing up this week with the last of three aerial applications of the biological insecticide Bacillus thuringiensis var. kurstaki (Btk).

Trapping remains a critical phase of ODA’s gypsy moth program. Without the traps, there is no good way to detect infestations early. By placing as many as four traps per square mile, chances of early detection are high. The success of ODA’s trapping program has kept Oregon from having to relive the mid-1980s when more than 19,000 gypsy moths were trapped and 225,000 acres were sprayed in Lane County alone.

“It is much cheaper to invest in a solid detection program that allows us to catch gypsy moths early and eradicate when the population is small rather than waiting for a huge outbreak like we had a few decades ago,” says Rogg.

Starting by June, gypsy moth traps will be placed in areas of host material- primarily deciduous trees attractive to the gypsy moth. ODA is starting its placement of traps a bit later than usual because of budget reductions. Most of the traps will be located on the west side of the state. However, some traps will be set in populated areas of Central and Eastern Oregon. Gypsy moths have been detected in the past in both Bend and Baker City.

The European gypsy moth- the kind most commonly found in Oregon- normally enters the state by hitching a ride on vehicles or outdoor household articles originating from infested areas of the Northeastern United States. As an increasing number of residents from the Northeast move to Oregon or visit, more moths may tag along. That explains why detections are often made in residential areas.

A higher density of traps will be placed in Eugene, the site of this year’s lone eradication project.

ODA declares a gypsy moth infestation officially eradicated after two years of zero catches.

This year, intensified trapping will also take place in areas where single detections of gypsy moth were made last year, including three separate sites in the Portland area and a new site southwest of Eugene. Dense trapping will also take place in Shady Cove in Jackson County- the site of 2008’s only gypsy moth eradication project. No moths were detected last summer in Shady Cove. Officials hope for similar results this summer.

There are indications that gypsy moth populations are relatively high in infested areas back east.

“Many eastern US states are currently spraying for gypsy moth in hopes of suppressing the populations,” says Rogg. “Our information is that the numbers are up and states are spraying quite a bit more than they did the previous year. We might expect more gypsy moths coming into Oregon with visitors, firewood, outdoor furniture, and recreational vehicles as people move to Oregon or visit.”

Oregonians shouldn’t have any trouble recognizing ODA’s gypsy moth detection effort this spring and summer. However, the traps are designed not to be overly noticeable, except to the moth itself. They are usually placed on a lower branch of primarily deciduous trees. As in the past, homeowners will be encouraged to not tamper with them as any damage may cost some valuable information. The traps are non-toxic and contain a sex pheromone that attracts the male moth. Inside the trap is a sticky surface similar to flypaper. The moth flies in and gets stuck to the inside surface. Throughout the summer, ODA crews will check the traps and will begin taking them down for the year in September.

Meanwhile, thousands of traps will be targeting invasive species that ODA wants to find if the bad bugs have indeed arrived in Oregon. Among the effort is placement of Japanese beetle traps, which look more like a plastic funnel with a can on the bottom.

“There are different colors and styles of traps, but they all do the same thing- they specifically target the insect they are meant to catch,” says Rogg.

While survey technicians place traps for the more traditional Oregon pests, they will also take a close look at trees and shrubs in the area for any suspicious signs of species yet to be found within the state’s borders. These include exotic wood boring insects such as Asian longhorned beetle and emerald ash borer- two species that have been detected back east and in the Midwest.

The threat from invasive species from around the world and other parts of the US has greatly increased over the years. It’s important for Oregonians to remember that the information obtained from this summer’s detection efforts will be useful in determining what eradication programs, if any, might take place next spring. While ODA would be delighted to not find any bad bugs in the months to come, the truth is new introductions of plant pests to Oregon are routine. If any of the invasive insects are out there, ODA wants to find them.

For more information, contact Helmuth Rogg at (503) 986-4662.


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