New Garlic Mustard Publication from the USDA Forest Service FHTET

The Forest Health Technology Enterprise Team was created by the Deputy Chief for State and Private Forestry in February 1995 to develop and deliver forest health technology services to field personnel in public and private organizations in support of the Forest Service's land ethic, to "promote the sustainability of ecosystems by ensuring their health, diversity, and productivity."

The Enterprise Team has two components. The core component, sponsored by Forest Health Protection, supports the Forest Service in meeting its legal mandate for the protection of forest health. The entrepreneurial component builds the team's capacity to fulfill its mission by providing services on a cost-reimbursable basis.
 

USDA Forest Service’s FHTET  has release a new publication on the biology and biological control of Garlic Mustard.

Biology and Biological Control of Garlic Mustard

Roger Becker, Esther Gerber, Hariet L. Hinz, Elizabeth Katovich, Brendon Panke, Richard Reardon, Mark Renz, and Laura Van Riper

FHTET-2012-05, November 2013

New Video on the Biological Control of the Brown Marmorated Stink Bug

Growers who use biological control methods could stop brown marmorated stink bug (BMSB), reduce costs, and put fewer chemicals into the environment. Learn to identify several native predators and parasitoids of BMSB in various crops and nurseries. Using less insecticide could help these natural enemies of BMSB. Methods such as cultural controls, trap cropping, and monitoring as part of a biological control strategy could keep BMSB populations in check.

See the new video on Biological Control of BMSB:

http://www.stopbmsb.org/video

New Biological Agent to Fight Invasive Weed

From Science Daily

Sep. 27, 2013 — University of Rhode Island entomologists reached a milestone in their efforts to control the invasive weed swallow-wort this month with the first release of a biological agent to fight the pest.

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Last week, the URI scientists, led by Professor Richard Casagrande and Research Associate Lisa Tewksbury, sent 500 larvae of the moth Hypena opulenta to partners in Canada for release in patches of swallow-wort near Ottawa.

"Swallow-wort is an aggressive invasive perennial weed that forms dense patches in a wide variety of habitats and may have negative impacts on monarch butterfly populations," said Casagrande. "But we believe that this moth has potential for keeping the weed in check."

A caterpillar of the moth Hypena opulenta feeds on the invasive weed black swallow-wort. (Credit: Photo courtesy of Richard Casagrande)

In 2006, URI doctoral student Aaron Weed discovered the moth larvae feeding on swallow-worts in southern Ukraine. He brought the larvae to partners at the Commonwealth Agricultural Bureau International (CABI) in Switzerland for rearing and initial testing. Research on the biology, impact, and host range of these insects was conducted at CABI and in the URI Insect Quarantine Laboratory over the next six years by Weed, now a postdoctoral researcher at Dartmouth College, and a second URI graduate student, Alex Hazlehurst.

After finding that the moth larvae will only attack and survive on swallow-worts, the URI scientists and colleagues in Canada and Switzerland petitioned the U.S. Department of Agriculture in 2012 to allow field release of this biological agent in North America. The review panel recommended it for USDA approval on September 4, 2013. The USDA has additional steps in its approval process before the agent can be released in the United States next spring, but the Canadian government granted permission for immediate release.

The URI team sent larvae to partners at Canada Agriculture late last week for the first release. According to Naomi Cappuccino of Carleton University, the release appeared successful and larvae were already pupating in preparation for the Canadian winter.

Pale and black swallow-wort were accidentally introduced into the United States from Europe over a century ago and have since spread throughout the Northeast and well into Canada and the Midwest. These toxic vining plants are major pasture pests and serious weeds in many agricultural, ornamental, and forest environments. In addition to their invasiveness, swallow-worts are closely related to milkweeds and threaten monarch butterfly populations. Monarchs readily lay eggs on swallow-worts, but all larvae that hatch on the plant perish.

"We believe that swallow-worts are particularly problematic in North America because they left all their natural enemies behind in Europe, and indeed, several European insects attack these plants in their native range," said Casagrande. "In addition to the moth just released, a second moth with populations found from Finland to Ukraine is under evaluation in our quarantine laboratory."

These agents will be compared with a related species under study by USDA scientists to select the next best species if there is need for further releases.

According to Casagrande, the approval and release of a new weed biocontrol agent is a major accomplishment for the URI program, as it required six years of study on the biology and impact of the agent as well as testing against 76 potential host plants, all of which came out favorable. The USDA has a very careful review process that so far this year has only recommended two new agents for release.
Biological control programs of this type require a great deal of cooperative research. In addition to the URI team, the project involved Ukrainian plant taxonomists, Swiss, French, and Canadian biocontrol specialists, and faculty and USDA researchers at Cornell University. It was funded by several grants from the USDA, U.S. Forest Service, and Agriculture Canada.

URI has several other biological control programs under way, including distributing and evaluating biological control agents against the lily leaf beetle, purple loosestrife, and mile-a-minute vine.

Tiny Wasp Could Be Stink Bug's Foe

Source: Oregon State University Press Release. agsci.oregonstate.edu Corvallis, Oregon (February 1, 2013)--As the brown marmorated stink bug spreads across the state, Oregon State University is studying how to use bug-on-bug warfare to stop this crop-damaging pest. The insect arrived in the eastern United States in the late 1990s and has since spread to more than 30 states. The non-native bug was found in Portland in 2004 and has since shown up in 13 Oregon counties, including all of the Willamette Valley. But populations in Oregon are still relatively low in most areas, according to OSU estimates. Although the pest has caused major commercial crop damage in many eastern states, so far it has had minimal impact on Northwest crops. To keep it that way, OSU researchers are looking to a non-pesticide solution: a tiny wasp imported from China. Smaller than a pinhead, the wasp, known as Trissolcus halyomorphae, lays its eggs in the brown marmorated stink bug's eggs. OSU researchers have produced a video showing this process. The potential release of the wasp in the field could still be years away as researchers need to first test its behavior in quarantine to determine if it discriminates between the brown marmorated stink bug's eggs and those of other species. Canada and Mexico must also agree to the wasp's introduction. "The problem with the introduction of biological control organisms is that bugs don't recognize borders like we do - we don’t want to release something that causes more harm than good," said entomologist Peter Shearer, who's leading OSU's stink bug research. "We want to do this right because rarely do we have an ample opportunity to deal with a problem that has the potential to be this bad." Oregon farmers fear the insect could severely affect crops if its numbers continue to swell. It has already been spotted near some large agricultural operations in Oregon. The bug isn't a picky eater, having shown a taste for more than 100 types of crops, including corn, wine grapes, hazelnuts, pears, apples and sweet cherries. It leaves behind discolored patches on the food, which is still safe to eat, but the cosmetic blemishes make the products largely worthless in the marketplace. "It's more of a list of what it doesn't eat than what it does feed on," said Vaughn Walton, an entomologist at OSU. "Identifying where the bug is found is an ongoing effort. Unfortunately, it has been detected in many of Oregon’s major agricultural areas and the populations are increasing. It looks like it could be a problem soon in some areas based on populations we found in 2012." OSU researchers are using this field data to plot an even more aggressive tracking strategy for 2013. In the meantime, Oregonians can assist the effort by reporting sightings. "A lot of the finds we’ve made the past few seasons are because of the public chipping in,” said Nik Wiman, a postdoctoral scientist at OSU's research center in Hermiston, who is studying the insect. “Without it, we would not have as good a picture of how the bug has distributed through the state.” In the winter, the brown marmorated stink bug seeks shelter indoors, often in attics, garages and dark, moist places. It can be confused with other insects, so the OSU Extension Service has published a two-page guide for the public on how to distinguish it from look-alikes. The document is also in Spanish. More information on the bug can be found on OSU's Brown Marmorated Stink Bug website. OSU is one of 11 institutions researching the brown marmorated stink bug in an effort funded by the U.S. Department of Agriculture, the Oregon Hazelnut Commission and the Oregon Wine Board. OSU graduate student Chris Hedstrom has also contributed to the project. Contact: Vaughn Walton 541-737-3485 waltonv@hort.oregonstate.edu

Feds scramble to halt stink bug invasion

 September 24, 2012 | The Examiner


The stink bug is back and in much bigger numbers than last year, giving fear to a potentially historic outbreak next year that has federal officials scrambling to deploy a killer that will stop the Chinese import's march into 38 states so far.

While last year's breakout was described as mild due to unfriendly weather, this fall's explosion of the brown marmorated stink bug is the second this year, a rare "second generation" of the bug that is now pouring into homes looking for a safe haven until they can emerge next spring to lay eggs.

"Populations have increased," Tracy Leskey, a lead research entomologist with the Agriculture Department, told Secrets. "This has been a very good year for the stink bug," added one of the nation's leading stink bug experts.

Orchard and vineyard farms and homeowners in the Washington region have reported massive numbers since last weekend. The bugs don't sting but do puncture fruits, making them quick to blemish and rot, and they often hide in cars, homes and even Craftsman sockets.

Leskey said that a strong fall second generation is a good indicator that next year's population will be even stronger. "A large population now means a potentially larger population will exit in the spring," she said. It's easy to see why: Each female stink bug carries 10 egg sacks with 28 eggs each.

But help might be on the way. Leskey and other researchers have expanded their list of potential killers to include baited traps and a native bug, the even uglier "wheelbug." Those are being studied at speeded up pace as a tiny wasp that is the stink bug's known killer in China.

"It will take multiple tactics" to stop the stink bug, said Leskey. But for now her advice to homeowners is a simple and smart one: "seal your homes."

Also to keep the public up to date on the fight against stink bugs, a research website has been created at http://www.stopbmsb.org.

Tiny wasps could curb a massive stink bug invasion

USDA researchers in Delaware are working to find a safe way to dispatch the region's newest pest

February 28, 2011|By Mary Carole McCauley, The Baltimore Sun

Newark, Del. — — Maryland's newest terrorist life form — the brown marmorated stink bug — may eventually meet its archnemesis in the form of a tiny prizefighter of a wasp from Asia.

The parasitic wasps that are being raised in quarantine in a Delaware laboratory are not glamorous-looking bugs. They are black, stocky and about the size of the comma in this sentence.

But they are uncommonly efficient at hunting down and injecting their offspring into stink bug egg masses. In true horror-movie fashion, the larvae consume the stink bugs from the inside out. When the wasps grow into adults, they chew their way out, procreate — and go on the hunt for more stink bug eggs.

"Tests have shown that these wasps will destroy up to 80 percent of the stink bug population," says Kim Hoelmer, the U.S. Dept. of Agriculture scientist in charge of the project. "They're efficient egg-stinging machines. For something so tiny, it's absolutely amazing the behaviors that are hard-wired into their little brains."

Stink bugs aren't a threat to human health. And if they were merely odoriferous and annoying, chances are that the nation's top bug experts wouldn't be going to so much trouble to locate and develop an insect assassin.

But not only do stink bugs represent an unprecedented threat to U.S. vegetable farms and orchards, they have the potential to drive up food prices just when the nation is struggling to emerge from a recession. Bug experts say that the Asian wasp may be one of their best tools for keeping the stink bug population down to a manageable buzz.

"I've never seen such a serious pest enter the U.S. agricultural system," said Tracy Lesky, research entomologist with the West Virginia-based Appalachian Fruit Research Station, "if only because they attack so many crops."

Populations of stink bugs have been increasing steadily in Maryland for the past five years, and are poised to invade the state in record numbers during the coming growing season.

"I think we're going to have a bumper crop," says Michael Raupp, an entomologist at the University of Maryland. "If 1 in 10 people had stink bugs in 2010, 9 in 10 people will have them in 2011."
Hoelmer and his team have been importing and studying the parasites since 2005.

Beetles Offer Effective Weed Control, but Native Vegetation Hard to Re-establish

(Nov 8, 2010)
Allen Press. Rangeland Ecology & Management.
 
With the help of the weed-eating flea beetle, researchers significantly reduced infestations of a non-native plant, Leafy Spurge, on Montana rangeland. This biological method of weed control worked effectively over the course of a 9-year study, but rather than native plants returning to flourish in the absence of leafy spurge, other non-native species became dominant in its place. By the study’s end in 2006, leafy spurge foliar cover was reduced 80% to 90% compared to 1998 assessments. While other vegetation did increase once this invader was controlled, another non-native plant, Poa spp., became the dominant species. The findings are published in the Rangeland Ecology & Management article Lack of Native Vegetation Recovery Following Biological Control of Leafy Spurge.

Fungus Tapped to Take on Kudzu

By Jan Suszkiw
July 16, 2009

Kudzu, "The Vine that Ate the South," could meet its match in a naturally occurring fungus that Agricultural Research Service (ARS) scientists have formulated as a biologically based herbicide.

By one estimate, kudzu spreads at the rate of 150,000 acres annually, easily outpacing the use of herbicide spraying and mowing, as well increasing the costs of these controls by $6 million annually.

But in Stoneville, Miss., ARS plant pathologist Doug Boyette and colleagues are testing a fungus named Myrothecium verrucaria, which infects kudzu with an astonishing speed of its own. In fact, the fungus works so quickly that kudzu plants sprayed with it in the morning start showing signs of damage by mid-afternoon, according to Boyette, with the ARS Southern Weed Science Research Unit in Stoneville.

He first began working with M. verrucaria in 1998, when a Louisiana Tech University scientist furnished him with isolates from diseased sicklepod specimens. In greenhouse experiments, spray formulations killed 100 percent of kudzu seedlings and 90 to 100 percent of older plants in outdoor trials. Myrothecium also worked its anti-kudzu magic under a wide range of conditions, including the absence of dew.

Additionally, host-range tests in 2005 showed that Myrothecium caused little or no injury to many of the woody plants known to occur in kudzu-infested habitats, including oak, cedar, pine, hickory, pecan, sassafras and blackberry.

A few companies expressed interest, but only if the fungus' production of toxins called trichothecenes could be reduced or stopped. Boyette's group examined several approaches, settling on a method of growing Myrothecium in a fermenter on a liquid diet instead of a solid one. Not only did this stop trichothecene production or reduce it to acceptable levels, the method also extended the fungus' shelf life and potency under field conditions.

Besides kudzu, Myrothecium also showed potential as a pre-emergence bioherbicide, controlling purslane and spurge in transplanted tomatoes.

Read more about the research in the July 2009 issue of Agricultural Research magazine.

Scientists research foreign bugs to help kill invasive plants in Midwest

By John Keilman, Chicago Tribune reporter


Across the Midwest, scientists are fighting an invasion of exotic, fast-spreading plants with imported insects that have one simple mission:

Eat and destroy.

It's an old agricultural tactic known as biological control, used here in recent years to dramatically cut down the scourge of purple loosestrife. Researchers are now looking into new bugs to sic on other plants in the rogues' gallery of Illinois vegetation: garlic mustard and buckthorn.

The insects travel and sustain themselves, so they can be a herbicide-free way to stop marauding plants on public and private property alike. For area homeowners it could mean getting control of their yards without putting down gallons of spray.

But the strategy is not without risk. Some alien insects are only moderately effective while others have become nuisances, chewing up flora they were not supposed to eat and spreading far beyond their intended boundaries.

It leaves even some practitioners of biological control uneasy about the potential consequences of unleashing new waves of miniature mercenaries.

"There's always that apprehension: Things are great now, but what will things be like [in the future]?" said Dan Thompson, an ecologist with the DuPage County Forest Preserve District. "Will something we bring in now haunt us down the road?"

Biological control uses an outsider to beat an outsider. When purple loosestrife, a flowering weed native to Europe, began taking over fields and forests in Illinois, officials turned to an insect that loved snacking on the plant back in the old countries.

Galerucella calmariensis, a tiny brown beetle, was released across the Chicago area in the mid-1990s. Its success was dramatic. The purple tide receded where it had crowded out native species, and plants such as wild iris, Joe Pye weed, blue joint grass and turtlehead began to return.

"There were literally thousands and thousands of acres of loosestrife up here 10 years ago," said Ken Klick, a restoration ecologist with the Lake County Forest Preserve. "And though it's still around, you don't see the monocultures you used to. We're very pleased."

The loosestrife campaign led to plans to take on other Midwestern plagues. The next target on the hit list is garlic mustard.

Imported from Western Europe as a delicacy in the 1860s, the piquant herb gradually spread out of control, covering forest floors like a carpet and smothering already established plants.

Within a year, researchers in Minnesota and New York hope to unleash a German weevil that devours garlic mustard from root to leaf. They've been looking at the bug for a decade, plying it with dozens of other plants to learn whether it might eat anything else.

"We want to make sure the only plant that will be attacked is garlic mustard," said Bernd Blossey, who is doing research at Cornell University.

Scientists have also looked for insects to combat teasel, an up-and-coming nuisance that has blanketed Illinois during the last 20 years. They have found contenders among European fleas and butterflies.

But the king of all plant invaders—buckthorn, an aggressively spreading shrub that starves native species of sunlight—might be the most resistant to an insect assault.

David Ragsdale, a professor of entomology at University of Minnesota who is researching buckthorn's insect enemies, said 50 species tested in Europe were rejected because they eat other vegetation. Meanwhile, the five he brought to his quarantine lab for further study—an aphidlike bug called a psyllid and various caterpillars—aren't voracious enough.

"The insects we've found so far are not exciting from my standpoint," he said. "They don't do a tremendous amount of damage [to buckthorn]."

He's still searching for other candidates, including insects that attack buckthorn found in Asia.

So far, the bugs that have been released in Illinois have been problem-free, but that's not always the case. The most notorious local example of biological control gone haywire is the multicolored Asian lady beetle, a bug brought to the U.S. as early as 1916 and used to control aphids on Southern pecan trees.

With no natural predators in this country—birds don't care for the foul-smelling goo within the beetles—they multiplied quickly, becoming an inescapable annoyance in Illinois and elsewhere.

More serious is the case of an Argentine moth that dines on prickly pear cactus. Australians imported the creature in the 1920s to curb the spread of the cactus, which had been planted as a living fence. The moth worked splendidly, said George Schneider, biological administrator with the Florida Department of Agriculture.

Then other countries started using the moth, and in 1989 it appeared unbidden in the Sunshine State, chewing its way through already rare cactus species. It has since spread west, and agricultural officials fear eco-disaster should it make it to cactus-rich regions in Texas and Mexico.

Researchers are trying to curb its spread by releasing irradiated moths that will mate with the cactus killers to produce sterile offspring, Schneider said.

Experts say biological control will expand as global trade, intentionally or otherwise, brings more invasive plants to the U.S. Some say the risks should be measured against the environmental damage of herbicides and the certain toll of inaction.

"Are you willing to go out every year and cut and cut and spray and spray just to hold the line, or can you look for some solution that lasts for a long time?" said Dave Voegtlin of the Illinois Natural History Survey, which helped to introduce the loosestrife-eating beetle.

"Exotics continue to come in. Our water and soil are just full of them. They're changing the dynamics of our system."

From the Chicago Tribune: China's ash trees may hold salvation for U.S. cousins

By Gerry Smith and Tara Malone | Tribune reporters


Glenn Weiler sounded like he was delivering a eulogy, speaking in the past tense used by arborists who now deem the ash tree's demise inevitable, its enemy unstoppable.

"Ash was so nice because it handled the tough soils," said Weiler, who stopped growing the species at his Zion tree nursery two years ago. "It's becoming a thing of the past, I think."

But some researchers still see a future for the ash tree, and they believe it lies somewhere in the Chinese countryside. Six years after the emerald ash borer was first spotted in the Midwest, researchers are turning their attention across the globe, to the region where the tiny, metallic-green beetle originated.

One ongoing effort—reminiscent of past efforts to rescue the American elm—is to identify Asian ash trees that have developed natural defenses against the pest, then develop a hybrid species for the American landscape that will withstand the devastating beetle.

"It's reflective of the idea that the emerald ash borer is here to stay and it's going to take a long-term solution," said Dan Herms, an associate professor of entomology at Ohio State University who is involved in the project.

Although still years from development, the pursuit of borer-resistant ash trees has become part of the evolving strategy for combating the ash borer, which has killed about 25 million trees across the Midwest and Canada.

Hope in Far East
Officials in Michigan found some hope in the Far East last fall, when they began unleashing tiny, stingless Chinese wasps that kill the pest's eggs and larvae.

And this spring, Illinois officials are rigging traps designed to snag the flying beetles after sweeping inspections and a state quarantine have helped contain their spread.

Also, researchers have been encouraged by the early success of a new pesticide that may become widely available this year. Researchers have found the pesticide, which contains the chemical emamectin benzoate, kills more than 99 percent of ash borer larvae in treated trees and virtually all adult ash borers that feed on them.

Meanwhile, evidence of the pest continues to emerge in ash trees across the Chicago area since first appearing two years ago in a Kane County subdivision. Last month, work crews with the Kane County Forest Preserve District cut down and burned nearly 100 trees infested with the ash borer.

Already, the telltale white larvae of the beetle have been spotted in ash trees everywhere from south suburban Hazel Crest to the tree-lined North Shore.

With few proven strategies for eradicating the ash borer, researchers across the Midwest are trying to find out how Asian ash trees manage to live with their enemy.

Later this year, Kris Bachtell plans to collect female ash tree seeds in China's Gansu province and join other researchers who are trying to identify, then replicate, the DNA in Asian ash trees with natural defenses against the ash borer.

"The best chance to find resistance is to go where the pests and plants co-evolved," said Bachtell, director of collections and grounds at the Morton Arboretum in Lisle.

The approach, which could take several years to yield results, was once used to revive another species after a similar scourge.

Learning from elms
During the 1950s, the American elm was nearly done in by Dutch elm disease, a plague that felled hundreds of trees in Chicago's Grant Park and nearly every elm on the campus of the University of Illinois at Urbana-Champaign.

But then researchers, led by the Morton Arboretum's George Ware, began experimenting with cross-breeding Asian elms in the late 1970s. Since then, the arboretum has introduced thousands of disease-resistant elms across the country.

Ware, a dendrologist at the arboretum, remains hopeful a similar effort could lead to a resurgence of the ash tree in the American landscape.

"It'd be a glorious thing if someone said, 'This is a species of ash that the ash borer simply does not like,' " he said. "The search is intense now, so I think there will be some kind of breakthrough."

Above all, officials said they've learned one important lesson from the outbreaks of both Dutch elm disease and the emerald ash borer: diversification.

Elms once represented about 40 percent of the tree population in metropolitan Chicago, but they were replaced after the Dutch elm outbreak by the ash tree, which makes up about one-fifth of Chicago's trees.

Now, as communities plant new trees where ash once stood, they're drawing from different species to guard against another pest destroying entire blocks of trees. Many suburbs cap the use of any single species at 5 percent of their total tree stock.

"When elm trees were removed and they replaced them with ash trees, there was a sense of urgency. They just wanted to replace them," said Jennifer Statz, a forester in Wilmette overseeing the removal and replacement of 2,855 ash trees on public lands during the next four years. "Now we've learned that's really not the wisest management choice."

Two years ago, when the emerald ash borer was discovered less than a mile from his Kane County tree nursery, Matt Zerby started bulldozing hundreds of ash trees. This month, Zerby plans to replace some of them with hybrid elm trees, hoping someday he'll be able to plant ash trees again.

"Who knows, maybe 40 years from now we'll have an emerald ash-borer resistant ash tree," Zerby said.