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Gypsy moth larva and a burlap 'trap".
First check the Web site gypsymoth.wi.gov. If it is gypsy moths or if you're not sure, call the statewide gypsy moth hotline, 1-800-642-MOTH/6684. All hotline calls are sent to county gypsy moth coordinators.
If you do have gypsy moths, talk to your neighbors and ask them to look for them on their lands.
"Landowners should then learn as much as they can about managing this pest in their yards and woodlands," said Anne Miller, Rock County land conservation specialist. "Management strategies are quite different for each land use."
Miller also has brochures and information at her office.
She can be reached at (608) 754-6617, Ext. 118, or amiller@co.rock.wi.us.
Gypsy moth larva and a burlap 'trap".
Gypsy moth defoliation.
Gypsy moth larva on leaf.
Rock County gypsy moth spray areas include 20 acres in Milton Township, about 30 acres in Janesville Township near the Rock River, two areas totally 103 acres in Center Township near Highway 14, 38 acres in Lustig Park in Janesville, 291 acres in Beloit Township along the river and 161 acres on the west side of Beloit.
Walworth County gypsy moth spray areas include 62 acres in East Troy Township, 66 acres south of Whitewater in Richmond Township, 31 acres in Bloomfield Township near Genoa City and seven areas totaling 345 acres around Geneva Lake.
JANESVILLE — Don't look up or you might get frass in your eyes.
In a few short weeks, gypsy moth caterpillars will be crunching their way through significant patches of south central Wisconsin's landscape.
Here's how bad it is:
The sound of masticating caterpillars, falling frass—caterpillar excrement—and bits of unwanted leaves floating to the ground combine to create a sound like a gentle rain shower.
"You can hear them eating," said Anne Miller, Rock County land conservation specialist.
Ick.
In the past 10 years, the state has stepped up its efforts to combat the pest, spraying selected areas and putting others under quarantine.
The eastern half of Wisconsin—including Green, Rock, Walworth and Jefferson counties—all are under quarantine. Nursery plants and trees, unprocessed logs, outdoor furniture and Christmas trees all must be found clean before they are shipped to areas that are free of gypsy moths.
Gypsy moths aren't just unsightly and obnoxious—they can destroy trees and decimate woodlands.
The caterpillars hatch in early May and begin eating immediately. They can defoliate a tree, leaving it vulnerable to diseases, insects and weather extremes that will kill it.
"It's generally not the gypsy moths that kill the tree—it's other stresses, like a previous year's drought," said Mark Guthmiller, state Department of Natural Resources regional gypsy moth suppression coordinator.
In Rock County, the state will spray seven areas ranging from Beloit to north of Milton. In Janesville, Lustig Park will be sprayed.
In Walworth County, the state will spray 11 areas, including three areas in Big Foot Beach State Park.
In cities, taxpayers pick of the cost of gypsy moth spraying.
In rural areas, individual homeowners are charged and estimated $32.50 an acre. And the state will spray only if there are 20 contiguous acres of infested woodlands. In a subdivision, the neighbors must agree to pay for their individual acreage before the spraying can take place.
When a single person or entity owns a large number of acres, the price might be adjusted to accommodate variations in terrain and other factors.
Bob Fisher, who owns 4 wooded acres north of Milton, has to battle the moths on his own.
"It's mainly all oaks," Fisher said. "Gypsy moths like oaks."
Fisher couldn't figure out quite what was wrong with his trees—or what those yellow-orange splotches were all over his woodpile.
"When Anne (Miller) came out here last fall, she was aghast," Fisher said. "I have these big wood piles—I heat my house with wood—and they were all over the wood piles."
Fisher cuts firewood in a couple of different places, and he thinks he might have brought the moth eggs to his home from another area.
All spring, he's been spraying the egg masses with a soybean-based oil to keep them from hatching. Now he's looking around for an extension to his sprayer so he can get at the egg masses farther up in the trees.
"If I don't keep at it, I'm going to lose the trees," Fischer said. "I can't mess around and wait."
Another area north of Milton will get sprayed: Camp Wakonda, the 66-acre recreation area owned by the Milton Seventh Day Baptist Church. On the front of the camp brochures it says "An outdoor Christian education ministry amid the great oaks in the beautiful Wisconsin countryside."
The wooded area features a lodge with kitchen and dining area and a few cabins.
Doug Lubke, church member and camp manager, said he first noticed "quite a large infestation" of larvae last summer.
"They were really just everywhere," Lubke said.
Rock Country forester Mary Ann Kroehn Buenzow gave him some literature about the gypsy moth, and Lubke realized he had a problem.
"Anne Miller said it was a 'moderate infestation,'" Lubke said. "They were really quite pesky. It got to the point where it was interfering with outdoor activities."
When volunteers from the church came out to oil egg masses, they found them everywhere: on picnic tables, all over buildings, and, of course, all up and down tree trunks.
About 40 of the 66 acres will be sprayed this spring, costing the church an estimated $1,000.
But it's worth it—gypsy moths could strip the landscape bare.
"Some of those trees are century-old oaks," Lubke said. "They're irreplaceable."
Gypsy moth quick hits
Spraying
Spraying for gypsy moths is tricky.
"We have a very limited window to spray in," said Mark Guthmiller, state Department of Natural Resources regional gypsy moth suppression coordinator.
In order for the spray to be the most effective:
-- The caterpillars should be less than ½-inch long and in the early stages of their growth cycles. About once a week, a caterpillar grows too large for its exoskeleton and molts. Caterpillars go through about five or six molts.
The spray is less effective on older caterpillars.
-- The leaves should have emerged from the trees, but not be too far along
-- The day has to be practically windless.
What's in that spray?
The active ingredient in gypsy moth spray is Bacillus thuringiensis, commonly called Bt.
Bt is a bacterium naturally found in the soil. When eaten, it causes the young caterpillars stomachs to disintegrate.
Bt is harmless to other animals including bees, birds, fish, humans and pets, according to the UW Extension and the Untied State Department of Agriculture. Home gardeners use Bt to combat cabbage moths.
The Organic Materials Review Institute has approved certain products containing Bt for use on organic farms.
When exposed to sunlight, Bt breaks down in a few days.
That said, Bt can harm other butterfly and moth species.
Before spraying, the DNR does a threatened and endangered species check, said Anne Miller, Rock County land conservation specialist.
If the area is home to such species, the state uses a Gypcheck product containing nucleopolyhedrosis virus as an alternative. The virus targets only gypsy moths
Gypcheck is not commercially available and is only produced in small quantities by the U.S. Forest Service. It's expensive to make and so is not routinely used.
Designing a predator to fight moths
The UW Extension is creating a new breed of super predators to fight gypsy moths: home and landowners.
The idea? Help people manage gypsy moths using simple pest-control methods.
First, however, the potential "super predators" must understand their foe's life cycle.
-- Mid April to early May
Larvae come out of their egg masses and climb to the top of the trees—or wherever their eggs were located—and suspend themselves from tiny threads.
Wind breaks the threads, sending tiny larvae out on the breeze. They usually land within 150 yards of their starting points. The practice is called "ballooning."
Tactic: Barrier bands.
Barrier bands are wrapped around trees and coated with a sticky material, capturing the caterpillars as they travel up the trees to eat or "balloon."
Barrier bands are available at hardware stores and garden centers, or you can make your own.
For a brief video on how to make sticky bands, go to www.uwex.edu/ces/gypsymoth.
-- Early May to mid June.
Caterpillars begin to eat.
And eat and eat and eat.
As they grow, they go through five or six molts, shedding their exoskeletons. Those different stages are called instars.
During the first three instars, caterpillars feed during the day. Around the fourth instar, they begin feeding at night, hiding under bark or leaf litter during the day.
Tactic: Burlap collection bands. Burlap is wrapped around trees then folded over, forming a skirt around the trunk. Caterpillars hide between the two burlap layers and at the end of the day can be collected and killed in a bucket of soapy water.
For instructions on how to make a burlap band, go to www.uwex.edu/ces/gypsymoth/collectionband.cfm.
-- July and August
Caterpillars form pupae and hunker down for one to two weeks to undergo their transformations to moths.
After emerging, moths mate and lay egg masses.
-- October to March
Egg masses overwinter.
Tactic: Scrape and spray, starting after the first hard frost.
Scrape egg masses into a bucket of soapy water and let sit for two days. Egg masses left on the ground will hatch the next spring.
Or, if the temperature is higher than 40 degrees, spray the egg masses with Golden Pest Spray, a soybean-based oil that kills the eggs.