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Rodrigo Krugner, an entomologist with the Agricultural Research Service (ARS) in Parlier, California, has found an innovative way to control insect pests in California vineyards: tapping into the vibrational signals they use as mating calls.

Krugner’s efforts have mainly focused on glassy-winged sharpshooters, which spread a bacterium that causes Pierce’s disease in vineyards and costs the California grape industry an estimated $104 million a year. Growers use chemical sprays to control the pests, but insecticides also kill beneficial insects, leave residues, and become less effective as the insects develop resistance.

Sometimes reaching a height of more than 100 feet tall with trunk diameters often well over 10 feet, the American chestnut was the giant of the eastern U.S. forests. There were once billions of them and their range stretched from Georgia and Alabama to Michigan, but the majestic tree was gone before forest science existed to document its role in the ecosystem. Notes left by early foresters including Gifford Pinchot, the founder and first chief of the USDA Forest Service, suggest that its ecological role was as impressive as the tree's size. Mature American chestnuts have been virtually extinct for decades. The tree's demise started with something called ink disease in the early 1800s, which steadily killed chestnut in the southern portion of its range. The final blow happened at the turn of the 20th century when a disease called chestnut blight swept through Eastern forests. But, after decades of work breeding trees, The American Chestnut Foundation, a partner in the Forest Service's effort to restore the tree, is close to being able to make a blight-resistant American chestnut available.

Laurel wilt has devastated plants in the Lauraceae family – redbay, sassafras, pondberry, avocado, and others – since it was first detected in the southeastern U.S. around 2002. There is no widespread, effective treatment for laurel wilt. Genetics research is focused on learning more about the pathogen's genetic structure in order to improve detection methods and screening for possible resistance in Lauraceae host species. "We have developed genetic markers to describe the population of the pathogen in the U.S.," says USDA Forest Service plant pathologist Tyler Dreaden. "Knowing which genotypes to use contributes to a quicker, more cost-effective resistance screening process." Dreaden led a new study to shed light on the genetic structure of the pathogen and its reproductive strategy. The research team included Marc Hughes at the University of Hawaii at Manoa, Randy Ploetz and Jason Smith at the University of Florida, and Adam Black, horticulture director of the Peckerwood Garden Conservation Foundation in Texas. Their findings were published in Forests.

Invasive insect and arthropod species make for a lot of scary headlines—think emerald ash borer, spotted lanternfly, and Asian longhorned tick, just to name a few. But success stories in invasive-species response are out there. They just need to be told. One of those success stories is the eradication of the European grapevine moth (Lobesia botrana) in northern California after it was found there in 2009. A cooperative, multipronged response effort kept infestations from running wild, and it was declared eradicated in 2016, two years after the last adult moth was caught in the region. The story of this effort is recounted, along with analysis of the invasion’s dynamics, in a study published in January in the Annals of the Entomological Society of America.

The Early Detection and Distribution Mapping System (EDDMapS) is a Web-based mapping system for documenting invasive species distribution. The majority of invasive species reporting in the U.S. occurs through or in cooperation with EDDMapS.

They’re coming to get you, spotted lanternflies and Japanese beetles! Detector canines—trained by USDA's Plant Protection and Quarantine (PPQ) program—are ready to sniff out these damaging invasive pests to detect them early and prevent their spread. These highly trained dogs represent some of the recent successes of our Agricultural Detector Canines strategic initiative. Its goal is to expand the use of detector dogs to enhance domestic pest surveys, detect pests early, and facilitate the trade of U.S. agricultural products.
See also: National Detector Dog Training Center

About 82% of the U.S. population lives in urban areas, and that number is growing. “Frequent travel to and from cities means that trees in urban areas have high rates of exposure to invasive species like the emerald ash borer,” says Frank Koch, a USDA Forest Service research ecologist and co-author of a study in the Journal of Applied Ecology about the impacts of invasive insects on urban trees.

Last month PPQ's Asian Longhorned Beetle (ALB) Eradication Program in Ohio celebrated another victory—the ALB quarantine is officially 7.5 square miles smaller! This invasive beetle from Asia is a destructive wood-boring pest that feeds on maple and other hardwoods, eventually killing them. After completing their final round of tree inspection surveys, the ALB staff reported no sign of the beetle in a portion of East Fork State Park in Clermont County, Ohio.

"Inspecting ALB host trees is painstaking work, and the staff meticulously survey for the pest," said ALB National Policy Manager Kathryn Bronsky. "It’s been three years since the last time we've lifted ALB quarantine restrictions in Ohio, and this is the first removal of the initial area placed under quarantine. That makes this success especially gratifying."

In recent decades, thousand cankers disease has become a concern for walnut growers and hardwood forest managers in the United States. A variety of measures have been investigated or developed to counter the disease. A study led by USDA Forest Service research entomologist Albert Mayfield and former University of Tennessee graduate student Jackson Audley looked at one measure: quarantine treatments. In an effort to stop the spread of the walnut twig beetle, certain states have prohibited the movement of regulated articles, including kiln-dried walnut lumber that still has its bark. The scientists investigated the risk of that type of lumber becoming colonized during movement to evaluate whether regulation of that product is necessary. Their paper was published in the Journal of Economic Entomology.

Forest Service scientists have published a guide synthesizing best practices for controlling these tiny bugs. It promotes a strategy of combining insecticide use with adelgid-eating insects.

Hunting for natural enemies of the red imported fire ant is paying off for Agricultural Research Service (ARS) scientists. Their latest discovery — a new virus found in fire ants from Argentina — has the potential of becoming a biological control agent against the red imported fire ants infesting the U.S.

Ailanthus altissima (tree-of-heaven) is a rapidly growing invasive tree species introduced to the United States nearly 200 years ago. Today, this species is a common invader in many forests across the nation. Scientists with the Northern Research Station have identified a unique biological control measure for managing Ailanthus—Verticillium nonalfalfae, a native soil-borne fungus. Check out this latest issue of Rooted in Research that explores how Verticillium can reduce Ailanthus populations.

Since 2002, forests in the southeastern U.S. have struggled against a disease called laurel wilt. In 18 years, laurel wilt has spread to 11 southeastern states and killed hundreds of millions of trees. A review article by USDA Forest Service scientist Rabiu Olatinwo reflects on the origins and spread of laurel wilt throughout the last several years. Olatinwo, a research plant pathologist at the SRS, published this research with recently retired plant pathologist Stephen Fraedrich and research entomologist Bud Mayfield in the journal Forests.

The National Integrated Pest Management Coordinating Committee (NIPMCC) has released a series of whitepapers explaining how pests threaten the security of the U.S. food supply, how an IPM approach offers the most effective means of managing pests, and why ongoing investment in IPM research and extension is critical to keeping pace with the ever-evolving nature of these threats. These new issue papers discuss role of IPM in combating resistance and invasive species, safeguarding food supply, and minimizing economic losses.

Spotted-wing drosophila (Drosophila suzukii), is an invasive fruit fly species that causes about $500 million in economic damage to fruit crops in the U.S. each year. A native to southeast Asia, it arrived in the U.S. in Hawaii in the 1980s and in the continental U.S. in California in 2008. It is now widespread through many parts of the U.S. and the world. In a new review article published last week in the Journal of Economic Entomology, Vaughn Walton, Ph.D., of Oregon State University and a multi-university team of experts have created a comprehensive look at how SWD management strategies are evolving to address these challenges.

The U.S. Department of Agriculture grant that funds part of Walton and colleagues SWD research stipulates that they work with industry influencers, and they have been doing this from the beginning. They bring technologies to industry and seek feedback on how well the technologies work in actual practice. "Federal funding is allowing us to listen to and serve our clients—the growers," Walton says. As the Journal of Economic Entomology paper details, many promising control strategies are being developed for this challenging and uniquely adaptable invasive species. With continued advances, researchers can hope that populations of SWD can be controlled and the damage they cause reduced.

The PPQ Mail Interception Dashboard can filter data to show where illegal shipments have been intercepted in the past and plot the locations across the United States. The dashboard will help us to better understand where violations are located; what products are being imported, from where, and how often; and the pathways that illegal packages travel to the United States.

The American chestnut (Castanea dentata) was a keystone tree species in the eastern U.S., once found in the forest overstory from Maine to Georgia. The loss of the "mighty giant" to chestnut blight (Cryphonectria parasitica), a fungal disease accidentally imported from Asia in the early 1900s, reduced the once dominant chestnuts to remnant understory sprouts. After eight years of field testing, USDA Forest Service research forester Stacy Clark and her colleagues evaluated blight resistance and survival of the backcross-generation American chestnut seedlings, known as BC3F3. Their results were published in Forest Ecology and Management.

Electronic noses are sensitive to a vast suite of volatile organic compounds that every living organism emits. A new USDA Forest Service study shows that e-noses can detect emerald ash borer (Agrilus planipennis) larvae lurking under the bark – an early, noninvasive detection method. "The results were quite spectacular," says Dan Wilson, a research plant pathologist and lead author of the study. The findings were published in the journal Biosensors.

In parts of the South, there are stories about an invasive floating weed, which forms such a dense mass that it enables small animals to walk across water. This weed, called giant salvinia, is an exotic fern from South America that invades ponds, lakes, and other waterways in the United States. It damages aquatic ecosystems by outgrowing and replacing native plants that provide food and habitat for native animals and waterfowl.

Agricultural Research Service (ARS) scientists are testing a naturally occurring fungus (Myrothecium spp.) against giant salvinia to help control it. Initial tests have found that the fungus stops this problematic weed from growing and even can kill it.

Meet the Honeysweet Plum: A virus-resistant plum that ARS hopes to bring to market soon. They are large and oblong with a very sweet, flavorful taste. ARS created the Honeysweet variety using RNAi, a biotechnology method that makes them immune to the plum pox virus. Plum pox infects stone fruit trees: plums, peaches, apricots and cherries. Once infected, the fruit discolors and falls from the tree prior to maturation. There is no natural, genetic resistance to the virus.