Purdue University - Extension - Forestry and Natural Resources
United States Department of Agriculture Animal and Plant Health Inspection Service Bulletin: USDA declares August Tree Check Month and urges public to look for Asian longhorned beetle.
WASHINGTON, July 23, 2019 — August is the height of summer, and it is also the best time to spot the Asian longhorned beetle (ALB) as it starts to emerge from trees. The U.S. Department of Agriculture (USDA) is asking the public to take five minutes to step outside and report any signs of this invasive pest. Checking trees for the beetle will help residents protect their own trees and better direct USDA’s efforts to eradicate this beetle from the United States.
“It’s important to look for signs of the beetle now, because it’s slow to spread during the early stages of an infestation,” said Josie Ryan, APHIS’ National Operations Manager for the ALB Eradication Program. “With the public’s help, we can target new areas where it has spread and provide a better chance of quickly containing it.”
The Asian longhorned beetle feeds on a wide variety of popular hardwood trees, including maple, birch, elm, willow, ash and poplar. It has already led to the loss of more than 180,000 trees. Active infestations are being fought in three areas of the country: Worcester County, MA, Long Island, NY (Nassau and Suffolk Counties), and Clermont County, Ohio.
“Homeowners need to know that infested trees do not recover and will eventually die, becoming safety hazards,” warned Ryan. “USDA removes infested trees as soon as possible because they can drop branches and even fall, especially during storms, and this keeps the pest from spreading to nearby healthy trees.”
The Asian longhorned beetle has distinctive markings that are easy to recognize:
After seeing signs of the beetle:
It is possible to eliminate this pest and USDA has been successfully doing so in several areas. Most recently, the agency declared Stonelick and Batavia Townships in Ohio to be free of the Asian longhorned beetle. We also eradicated the beetle from Illinois, New Jersey, Boston, MA, and parts of New York. The New York City boroughs of Brooklyn and Queens are in the final stages of eradication.
For more information about the Asian longhorned beetle, other ways to keep it from spreading—such as not moving firewood—and eradication program activities, visit USDA Animal and Plant Health Inspection Service. For local inquiries or to speak to your State Plant Health Director, call 1-866-702-9938.
Other Resources:
Report Invasive Species, Purdue Agriculture & Indiana Invasive Species Council
Great Lakes Early Detection Network, Bugwood Apps
New Hope for Fighting Ash Borer, Got Nature? Blog
Mile-a-Minute Invasive Vine Found Indiana, Got Nature? Blog
Sericea Lespedeza: Plague on the Prairie, Got Nature? Blog
Invasive Plants: Impact on Environment and People, The Education Store, Purdue Extension
Invasive Plant Species in Hardwood Tree Plantations, The Education Store
Invasive Plant Species: Callery Pear, Purdue Extension The Education Store
United States Department of Agriculture Animal and Plant Health Inspection Service
Purdue Landscape Report: When was the last time you really looked at your trees? It’s all too easy to just
enjoy their cool shade and the sound of their leaves, but if you don’t know what to look for you could miss deadly diseases or dastardly demons lurking in their leaves and branches. A quick check can help you stop a problem before it kills your tree or your local forest!
National Tree Check Month is the perfect time to make sure your tree is in tip-top shape! Our checklist will help you spot early warning signs of native pests and pathogens and invasive pests like Asian longhorned beetle, spotted lanternfly, and sudden oak death. You can stop invasive pests in their tracks by reporting them if you see them.
Is your tree healthy and normal?
Start by making sure you know the type of tree you have. Is it a deciduous tree like an oak or maple? Or is it an evergreen that like a spruce or a pine? Don’t worry about exactly what species it is. It’s enough for you to have a general sense of what the tree should look like when it’s healthy.
Check the leaves
Check the trunk and branches
Now what? If you answered YES to any of the questions above, there’s a good chance something is wrong. To decide if and how you should treat or report the problem, you’ll need to have a tentative diagnosis. Luckily, there are many ways to get one!
Know the tree species? Use the Purdue Tree Doctor to get a diagnosis and a recommendation on whether treating or reporting is needed. This app allows you to flip through photos of problem plagued leaves, branches and trunks to help you rapidly identify the problem. If you have an invasive pest, it will guide you how to report it.
Don’t know the tree species and still need help? Reach out to local experts. We’re happy to help!
Confused but think something is TERRIBLY WRONG? Contact Purdue’s Exotic Forest Pest Educator, report online, or call 1-866-NOEXOTIC.
Resources:
Trees and Storms, The Education Store, Purdue Extension’s resource center
Why Is My Tree Dying?, The Education Store
Caring for storm-damaged trees/How to Acidify Soil in the Yard, In the Grow, Purdue Extension
Tree Risk Management, The Education Store
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Installation: Process and Practices, The Education Store
Tree Planting Part 1 & Tree Planting Part 2, videos, The Education Store
Cockroaches are serious threats to human health. They carry dozens of types of bacteria, such as E. coli and salmonella, that can sicken people. And the saliva, feces and body parts they leave behind may not only trigger allergies and asthma but could cause the condition in some children.

A German cockroach feeds on an insecticide in the laboratory portion of a Purdue University study that determined the insects are gaining cross-resistance to multiple insecticides at one time. (Photo by John Obermeyer/Purdue Entomology)
A Purdue University study led by Michael Scharf, professor and O.W. Rollins/Orkin Chair in the Department of Entomology, now finds evidence that German cockroaches (Blattella germanica L.) are becoming more difficult to eliminate as they develop cross-resistance to exterminators’ best insecticides. The problem is especially prevalent in urban areas and in low-income or federally subsidized housing where resources to effectively combat the pests aren’t as available.
“This is a previously unrealized challenge in cockroaches,” said Scharf, whose findings were published in the journal Scientific Reports. “Cockroaches developing resistance to multiple classes of insecticides at once will make controlling these pests almost impossible with chemicals alone.”
Each class of insecticide works in a different way to kill cockroaches. Exterminators will often use insecticides that are a mixture of multiple classes or change classes from treatment to treatment. The hope is that even if a small percentage of cockroaches is resistant to one class, insecticides from other classes will eliminate them.
Scharf and his study co-authors set out to test those methods at multi-unit buildings in Indiana and Illinois over six months. In one treatment, three insecticides from different classes were rotated into use each month for three months and then repeated. In the second, they used a mixture of two insecticides from different classes for six months. In the third, they chose an insecticide to which cockroaches had low-level starting resistance and used it the entire time.
In each location, cockroaches were captured before the study and lab-tested to determine the most effective insecticides for each treatment, setting up the scientists for the best possible outcomes.
“If you have the ability to test the roaches first and pick an insecticide that has low resistance, that ups the odds,” Scharf said. “But even then, we had trouble controlling populations.”
For full article: Rapid cross-resistance bringing cockroaches closer to invincibility.
Resources
Report Invasive Species, Purdue Agriculture & Indiana Invasive Species Council
Purdue experts encourage ‘citizen scientists’ to report invasive species, Purdue Agriculture News
New Hope for Fighting Ash Borer, Got Nature? Blog, Purdue Forestry and Natural Resources
Mile-a-Minute Invasive Vine Found Indiana, Got Nature? Blog
Sericea Lespedeza: Plague on the Prairie, Got Nature? Blog
Michael E. Scharf, Professor and O.W. Rollins/Orkin Chair
Purdue Department of Entomology
Brian J. Wallheimer, Science Writer
Purdue College of Agriculture

Scientists from Purdue’s Tick INsiders program, Lauren Hagen (left) and Maria Muriga (right), drag and check tick cloths at Tippecanoe River State Park in 2018. The program is looking for high school students and citizen scientists interested in helping with tick collections this year. (Tick INsiders photo)
Purdue University’s Tick INsiders program is looking for Indiana high school students and other Indiana residents willing to roll down their sleeves to get involved in a citizen science project.
Cate Hill, a Purdue professor of entomology, leads this effort to analyze the bacteria and viruses in Indiana’s ticks to build an understanding of what they are carrying and how that might impact human health. To do that, she needs volunteers to collect ticks from all over the state.
This year the Tick INsiders program will provide training for up to 50 students. Citizen scientists are also now welcome to collect and send ticks to Hill’s lab.
“It’s really important work. The Centers for Disease Control and Prevention reports that human cases of tick-borne diseases doubled from 2004 to 2016. If we’re going to get a handle on that and develop strategies for reducing tick bites and treating patients, we need to know where our ticks are and what our ticks are carrying around inside them,” Hill said. “That means we need a lot of ticks, and we need help collecting them.”
Three species of ticks – the blacklegged or deer tick, the lone star tick and the American dog tick – are found in Indiana. These ticks can transmit multiple pathogens, nine of which are known to cause human illnesses, though not all have been identified in Indiana. The Indiana State Department of Health reports more than 100 cases of Lyme disease each year and dozens of cases of Ehrlichiosis, anaplasmosis and Rocky Mountain spotted fever.
Research suggests that ticks can carry a cocktail of microbes – bacteria and viruses – that can sicken bite victims and may work in concert to affect the severity of an illness and human immune response.
“Not all tick bites are the same. We don’t know what is passed from a tick to a human each time someone is bitten, which means that health care professionals may need to consider multiple tick-borne pathogens in a person who has been bitten by a tick,” Hill said. “This program improves our knowledge so that we can improve our outcomes.”
Indiana residents interested in participating can collect ticks and send them to Hill’s lab for analysis. Videos on safe and proper collection techniques, as well as how to send ticks will be at Tick INsiders.
For full article, see Purdue Agriculture News.
Resources
Ticks 101: A Quick Start Guide to Indiana Tick Vectors, The Education Store – Extension Resource
The Biology and Medical Importance of Ticks in Indiana, The Education Store
Mosquitoes, Purdue Extension Entomology
One Small Bite: One Large Problem, Got Nature?, Purdue Extension-Forestry and Natural Resources
Mosquitoes and ticks – little pests carry big risks, Got Nature?
Catherine A Hill, Professor of Entomology/Vector Biology
Purdue University Department of Entomology
Emerald ash borer (EAB), the most destructive forest pest to enter North America has left hundreds of millions of dead ash trees in its wake. Although this pest has been found throughout our state, many of Indiana’s ash trees are still alive, or dead and still standing. Ash trees killed by emerald ash borer, become extremely brittle and break easily as they decline. Branches can fall on people and property in snowstorms, with a light breeze, or even on a calm clear day. Danger could be hanging over your head in the street, in the forest, and even in your backyard.
Why does emerald ash borer make ash trees so brittle?
Unlike elms, oaks, and maples, ash trees use a thin ring of conducting tissue to supply water from the roots to the entire tree. Emerald ash borer grubs will damage these functional water pipes as they chew just beneath the bark inside trunks and branches. This causes the tree to dry quickly and the structural wood to become prone to cracking. Internal breaks in the structural wood that bear the weight of the tree are often hidden from view by tree bark. As such, limbs can break and fall at any point along the branch at any time. It is not uncommon to have sizable limbs snap 30 feet off the ground on a calm day.
The threat of falling limbs is not limited to just dead ash. A comparative study of ash trees conducted in Ohio shows that structural integrity of ash trees can begin to decline even when trees are mostly green and have two thirds of the canopy still intact.
What should I do to protect myself from falling ash trees and limbs?
If your tree has lost less than 30% of its canopy hire a professional to protect the tree.
If the tree has lost more than 30% of the canopy, make plans to remove it. Delaying removal allows the tree to become more brittle and the problem more dangerous. Remember, EAB causes progressively more injury to ash trees as time goes on. The dead parts never come back to life.
If you have been treating your tree continue to do so.
How should I remove the tree?
To minimize risk of harm, hire a trained professional who has experience removing emerald ash borer damaged trees. The International Society of Arboriculture maintains a directory of Certified Arborists and their credentials. They can help find an arborist near you. Always get bids from more than one contractor. Be sure your contractor is insured and bonded in case of an accident. Professionals are happy to share this information.
Some homeowners might be hesitant to remove dead ash trees because they provide valuable habitat for a range of woodland animals and mushrooms. However, we do not recommend keeping them standing unless you can guarantee that no people, domesticated animals, or property will ever be in their path if they fall. If you have a dead tree that can’t be felled right away or ever, stay away from it until after it has fallen.
Article courtesy of the Landscape Report.
Resources:
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension-FNR
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Cost Calculator – Purdue Extension Entomology
Lindsey Purcell, Urban Forestry Specialist
Purdue Forestry and Natural Resources
Elizabeth Barnes, Exotic Forest Pest Educator
Purdue Entomology
Cliff Sadof, Professor, Ornamental, Pest Management
Purdue Entomology Extension Coordinator
Jennifer Koch, and other researchers with the U.S. Forest Service, has spent the last several years studying what are known as lingering ash – trees that have fared much better against the emerald ash borer. The invasive beetle, which came to North America from Asia about 20 years ago, has killed millions of ash trees around the Midwest.

An adult emerald ash borer feeds off a leaf. (Purdue University Department of Entomology photo/John Obermeyer)
But for reasons that researchers are learning more about, some trees have survived.
Koch says they’ve identified at least two reasons why. Lingering ash seem to attract fewer hungry adult ash borers, which means they’re less likely to become homes to eggs. And when eggs do hatch on lingering ash trees, they tend to be smaller and have a higher mortality rate.
Those are extremely valuable characteristic for modern ash trees, so Koch is making sure they get passed on through cloning. Not genetic modification, but rather clonal duplicates of lingering ash literally cut from part of the parent tree.
Maybe most importantly, Koch says the cloned trees appear to be even more resistant to the ash borer. With their cloned trees healthy and growing, researchers are waiting on the next generation of seeds to see if they’re even more resistant than their cloned parents.
Koch says they plan to add more lingering ash seedlings into their on-site orchard this year. Ash trees planted from seed typically take seven to 10 years to begin giving off seeds of their own, so it could be another decade before Koch knows just how successful their ash tree breeding program can be.
See full article: Attack Of The Clones: Ohio Researchers Find New Hope For Fighting Ash Borer, WOSU Public Media
Resources:
Question: What options do we have to treat our ash trees against the Emerald Ash Borer?, Got Nature?, Purdue Extension-FNR
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature?, Purdue Extension-FNR
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Tools & Resources – Purdue Extension Entomology
WOSU Radio, Columbus, Ohio
Imidacloprid, the active ingredient works by killing adults when they feed in the summer before they lay eggs. It slowly kills the two youngest stages of grubs that feed beneath the bark. The later and larger two stages are not killed. Material applied in the fall does not start killing beetles until spring. It takes twice the dose in the fall to get the same effect as a spring application. Trees with a trunk diameter of >20 inches at 4.5 ft above the ground can’t be controlled with imidacloprid.
So if your trees are starting to die I would suggest you skip the fall application of imidacloprid and switch to a professional injection of emamectin benzoate. See Management of EAB, Purdue Extension Emerald Ash Borer, for more information.
Resources:
What to do about emerald ash borer, Got Nature?, Purdue Extension-FNR
Emerald Ash Borer, Purdue Extension-Entomology
EAB research: Saving trees early less costly than replacing them, Purdue Agriculture News
Cliff Sadof
Purdue Extension – Entomology

Figure 1: Spongy moth caterpillar, credit to John Obermeyer.
In the late 1860s, French scientist Étienne Trouvelot brought over a seemingly harmless insect from Europe called the gypsy moth to conduct breeding experiments with American moths. When they escaped his backyard and entered into an ecosystem without their native predators, their population exploded. 150 years later, these moths are still a destructive forest pest in Indiana and other states. Every year an effort is made to attempt to curb their population. This year, the Indiana Department of Natural Resources will continue the fight to save our forests from these invasive insects.
Phase one consists of a crop dusting of bacterial chemical spray over the gypsy moth caterpillars’ food sources. This spray is harmless to humans and native wildlife, but is lethal to the caterpillars. Later in the summer, a pheromone will be dispersed over the moths, disrupting the mating process and causing fatal exhaustion.
This huge undertaking isn’t estimated to stop the gypsy moth – in fact, state entomologists don’t see an end in sight. We can only continue to manage this forest pest and aim for reducing populations to a level where local predators can manage them on their own. Indiana citizens can help combat this pest by understanding the gypsy moth problem and learning about its management.
For more information and when the aerial treatments will be conducted in your county visit the Indiana Department of Natural Resources, 2017 Indiana Gypsy Moth Treatment Program. For Tippecanoe view Purdue News.
Resources:
Gypsy Moth (Spongy Moth) website, Purdue Extension-Entomology
Spongy Moth – Indiana Department of Natural Resources
The Gypsy Moth in Indiana – The Education Store, Purdue Extension resource center
Indiana Department of Natural Resources
This comprehensive written abstract titled Tools for Staging and Managing Emerald Ash Borer in the Urban Forest shares research gathered in an eight-year period with a variety of management strategies.
Advances in control can help municipal foresters save ash trees from emerald ash borer (EAB) [Agrilus planipennis (Fairmaire)]
in urban forests. Although ash trees of any size can be protected from this pest, cities often do not implement programs because they fail to recognize and act o incipient populations of EAB. In this study, researchers develop a model for predicting ash mortality over an eight-year period, and validated with data from the removal of >14,000 ash trees killed by EAB in Fort Wayne, Indiana, U.S. researchers then developed a sampling scheme to help foresters map their ash trees along the expected progression of ash decline. This model was then used to modify a web-based EAB cost calculator that compares discounted annual and cumulative costs of implementing a variety of management strategies. It was determined that strategies that most heavily relied on saving ash trees were less expensive and produced a larger forest than those strategies that mostly removed and replaced ash trees. Ratios of total discounted costs to discounted cumulative benefits of strategies that saved most ash trees were over two-thirds lower than strategies of proactive tree removal and replacement. Delaying implementation of an ash management program until damage would be visible and more obvious to the community (Year 5 of the model) decreased the cost–benefit ratio by <5%. Thus, delays that rely on the abundance of locally damaged trees to bolster community support do not necessarily diminish the utility of implementing a control strategy.
For full article: Tools for Staging and Managing Emerald Ash Borer
Resources:
Tree Doctor App, The App Store
Invasive Species – Indiana Department of Natural Resources (IDNR)
Ask an Expert – Purdue Extension-Forestry and Natural Resources
Indiana Invasive Species Council – Includes: IDNR, Purdue Department of Entomology and Professional Partners
Great Lakes Early Detection Network App (GLEDN) – The Center for Invasive Species & Ecosystem Health
National Invasive Species Awareness Week: February 27-March 3, 2017
Invasive Species Week a reminder to watch for destructive pests, Purdue entomologist says – Purdue Agriculture News
Cliff Sadof, Professor
Purdue University Department of Entomology
Matt Ginzel, Associate Professor
Purdue University Department of Forestry and Natural Resources & Department of Entomology
The Forest Pest Outreach and Survey Project at Purdue reminds us that early detection is the best way to slow the spread of invasive species. You can report invasive species by calling the Invasive Species hotline at 1-866-NO-EXOTIC (1-866-663-9684) or using the free Great Lakes Early Detection Network smartphone app, which can be downloaded on iTunes or Google Play. View video to see how easy it is to use the app, Great Lakes Early Detection Network App (GLEDN).
If you’re interested in learning more about invasive pests and how to report them, sign up for one of our free Early Detector Training workshops!
National Invasive Species Awareness Week: February 27-March 3, 2017.
Resources:
Invasive Species – Indiana Department of Natural Resources (IDNR)
Ask an Expert – Purdue Extension-Forestry and Natural Resources
Indiana Invasive Species Council – Includes: IDNR, Purdue Department of Entomology and Professional Partners
Invasive Species Week a reminder to watch for destructive pests, Purdue entomologist says – Purdue Agriculture News
Sara Stack, MS student
Purdue Department of Entomology