Got Nature? Blog

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

• Are the leaves yellow, red or brown?
• Are they spotted or discolored?
• Do the leaves look distorted or disfigured?
• Is there a sticky liquid on the leaves?
• Do the leaves appear wet, or give off a foul odor?
• Are leaves missing?
• Are parts of the leaves chewed?

Check the trunk and branches

• Are there holes or splits in the trunk or branches?
• Is the bark peeling from a tree that shouldn’t shed its bark?
• Are there tunnels or unusual patterns under the bark?
• Is there sawdust on or under the tree?
• Is there sap oozing down the tree?
• Does the sap have a bad odor?
• Do sticky drops fall on you when you stand under the tree? You might have spotted lanternfly. Please report it right away!

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!

• Purdue Cooperative Extension Service (https://extension.purdue.edu/) can answer your questions or direct you to a local tree care professional with the right expertise.
• Contact an arborist who can give you an assessment of your tree and specific treatment recommendations (https://www.treesaregood.org/findanarborist).

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: Understanding Damage, Risk and Recovery – Got Nature? Blog, Purdue Extension – FNR
Why Is My Tree Dying? – Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
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

Purdue Extension – Entomology

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With all of the recent rain we have had throughout the state, I have received several inquiries about effects on wildlife and what we can expect.  While some flooding is natural in low areas and wildlife are adapted to respond, extreme flooding can impact wildlife. Flood waters can wash away nests or drown developing or very young animals for those living in low-lying areas. For example, heavy spring rains can reduce nest success of wild turkeys.

In many cases, wildlife will adapt by simply moving to higher ground. I tend to get an increase in inquiries about snakes after flooding. They begin showing up in neighborhood homes when they have never been observed in years past. Certainly our environment changes over time and wildlife can and do respond to these changes.  However, sudden changes are likely due to a response of snakes moving to drier ground. The good news is this and other similar displacement of wildlife is usually temporary.

What can we do?  I’m afraid not much for our currently flooded friends. However, in the long-term, times like this reinforce the need to create and enhance quality wildlife habitat. Providing wildlife with quality habitat that contains the necessary food, cover and water resources gives them a fighting chance to deal with issues that inevitably arise. In addition, wetlands that landowners build and restore on their properties not only enhance wildlife habitat, but also help retain moderate flood waters and recharge groundwater supplies.

If some unwanted wildlife has overstayed their welcome in and around your home, check out the Purdue Education Store publication, Considerations for Trapping Nuisance Wildlife with Box Traps. If you think you have found a sick or injured animal, you can find a list of licensed Wild Animal Rehabilitators in your area on the DNR Division of Fish and Wildlife’s Orphaned and Injured webpage. In Indiana, wildlife rehabilitators have necessary state and federal permits to house and care for sick or injured wild animals.

Additional Resources
Preventing Wildlife Damage – Do You Need a Permit? The Education Store, Purdue Extension
The Basics of Managing Wildlife on Agricultural Lands​, The Education Store, Purdue Extension

Brian J. MacGowan, Extension Wildlife Specialist
Department of Forestry and Natural Resources, Purdue University

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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 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

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The Illinois-Indiana Sea Grant and Purdue Forestry and Natural Resources Extension have recently released a new publication through The Education Store. This collaborative publication is a visual identification guide on salmon and trout of the Great Lakes.

The Great Lakes are home to eight species of salmon and trout. These species can be difficult to distinguish from each other as they overlap in their distributions and change appearance depending on their habitat and the time of year. This illustrated, peer-reviewed, two-page guide, courtesy of the Great Lakes Sea Grant Network, shows important body features and helpful tips to identify and distinguish between salmon and trout species in the Great Lakes.

View the Salmon and Trout of the Great Lakes: A Visual Identification Guide on The Education Store-Purdue Extension. See below for other related publications and websites.

Resources
A Fish Farmer’s Guide to Understanding Water Quality, National Oceanic and Atmospheric Administration
Pond Management: Stocking Fish in Indiana Ponds, The Education Store
The Nature of Teaching: Adaptations for Aquatic Amphibians, The Education Store
DNR Fish Identification Form, Indiana Department of Natural Resources
Illinois-Indiana Sea Grant, IISG Homepage

Mitchell Zischke, Clinical Assistant Professor
Purdue University Department of Forestry and Natural Resources

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Sudden oak death, as the name suggests, is a disease that is capable of rapidly killing certain species of oaks.  It was first identified in California, in 1995. Two years earlier it was identified in Germany and the Netherlands, killing rhododendron. Because the pathogen originally infected and killed tanoaks, an undesirable, understory scrub tree, it generated little interest until other, more desirable oaks species began dying.  However, by this point, the disease was well established and eradication no longer an option, with millions of oak trees killed by the disease.  Currently, over 120 hosts in addition to oaks have been identified, and more continue to be added to this list.  What is most unusual about sudden oak death is the severity of disease symptoms coupled with the broad host range of the pathogen. This leads to difficulty in diagnosing and managing this disease.

What causes this disease?
The pathogen that causes SOD is Phytophthora ramorum (pronounced Fī-toff-thor-ă  ră-mor-ǔm).  This pathogen belongs to a group of organisms in the Kingdom Chromista, and has characteristics similar to fungi, plants and animals.  It spreads throughout the plant by hyphal threads (like fungi), produces spores (like fungi) that have flagella and swim through water (like animals), but its cell wall is made up of cellulose (like plants). When conditions dry up, Phytophthora can produce thick walled sexual spores called oospores, or asexual chlamydospores. Because P. ramorum is not a ‘true’ fungus, many fungicides labeled for control of other fungal diseases are not effective against it.

With such a broad range of plant hosts, it is important to stress that P. ramorum affects different species in different ways. Identification must be confirmed in the laboratory and cannot be identified on field symptoms alone. Many common landscape shrubs are also infected by other endemic Phytophthora species, and symptoms look similar. Boring insects and other root rots may be mistaken for this disease. For this reason, all Phytophthora infections should be screened by the Purdue Plant and Pest Diagnostic Laboratory.

What are the symptoms of SOD?
To understand this disease, it is important to recognize that there are two categories of hosts: bark canker hosts and foliar hosts. Further complicating this is the fact that oaks are divided into three subgroups, and only the red oak group are susceptible to this pathogen. Of our 17 oak species in Indiana, half are potentially, or known to be susceptible, and include black, blackjack, cherrybark, Northern pin, pin, red, scarlet, and Shumard oaks. Diagnostic symptoms of infected red oaks include oozing sap and red-brown cankers that often leading to death.

Our concern right now is on ‘the other’ hosts. Despite its name, sudden oak death primarily spreads through foliar hosts that are sold throughout the United States. Foliar hosts include rhododendrons, azalea, viburnum, lilac, and periwinkle (Vinca minor).

These hosts (and many others) are infected via the leaves and small branches. These infections rarely cause death, and can be mistaken for sunscald, twig canker, and dieback caused by other pathogens, including native Phytophthora species. Although symptoms from these infections are not severe, and are rarely fatal, the infections produce enormous numbers of spores that can infect neighboring, susceptible oaks—and other plant species. For this reason, we are asking people to examine any rhododendrons (or other co-mingled hosts like azalea, viburnum and lilac) purchased this spring from Walmart and Rural King, while the disease may still be controlled and the pathogen contained. Although this disease doesn’t look like much on rhododendron or lilac, its ability to spread to oaks and kill them is what makes it so devastating. These shrubs play a key role in the spread of P. ramorum, acting as a breeding ground for spores (inoculum) that can spread through water, wind-driven rain, plant material, or human activity. Oaks are considered terminal hosts, since the pathogen does not readily spread from intact bark cankers; they become infected only when exposed to spores produced on the leaves and twigs of neighboring plants.

For full article and photos view: Purdue Landscape Report

Other resources:
Sudden Oak Death, California Oak Mortality Task Force
Sudden Oak Death, Indiana Department of Natural Resources
White Oak, The Education Store, Purdue Extension resource center
Planting Forest Trees and Shrubs in Indiana, The Education Store
Successful Oak and Hickory Regeneration, The Hardwood Ecosystem Experiment: 2006-2016, The Education Store
Find a Certified Arborist, International Society of Arboriculture

Janna Beckerman, Professor
Purdue Botany and Plant Pathology

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Question: I have noticed that a lot of very mature (> 80 ft) sycamore trees look ill. They don’t seem to have as many leaves, or as large as they usually get and some have already turned brown and died. There are at least 2 in my 5 acres of woods and have noticed the same with other sycamores while driving from Mooresville to Indianapolis. Is there a certain blight/canker/pest that is damaging sycamores this year?

Answer: I have also noticed that many sycamores appear relatively bare and may have brown or wilted leaves on the stems and littering the ground around the trees. The culprit is sycamore anthracnose, a fungal disease that causes damage and death of leaves as well as stem cankers. Sycamore anthracnose symptoms can be severe when we have cool, moist spring weather at the time of bud-break and leaf emergence , but healthy trees generally recover and put on new leaf area once the environmental conditions that favor the disease change to the warmer, drier conditions of late spring and summer.

Normally, the best management practices for sycamore anthracnose are patience and maintaining good tree health. The disease cycle is dependent on cool, moist spring weather, so it will run its course by late spring or summer when the average temperatures rise. Trees that are repeatedly defoliated could be reduced in vigor and be more susceptible to other problems, so steps to promote good tree health can be used as a preventative measure.

Resources:
Fertilizing Woody Plants – The Education Store, Purdue Extension Resource Center
Diseases of Landscape Plants (leaf diseases) – The Education Store
Sycamore – The Education Store
Hardwood Lumber and Veneer Series – The Education Store
Anthracnose of Shade Trees – Purdue Plant and Pest Diagnostic Laboratory
Purdue Plant Doctor App- Purdue Extension

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

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The Purdue Extension-Nature of Teaching has recently released a new publication through The Education Store. The Nature of Teaching provides free Indiana Academic Standard-based lesson plans for students in grades second through sixth to guide them on how to help maintain a healthy environment.

Understanding adaptations for aquatic amphibians can help humans learn more about healthy ecosystems. Through this educational unit, students will be able to explain how amphibian adaptations benefit survival, describe the importance of Eastern Hellbender adaptations, and identify impacts that humans have on aquatic amphibians.

These packed lesson plans are great resources for school teachers, parents, 4-H leaders and other natural resource educators. View the Adaptations for Aquatic Amphibians for the latest installment in the Nature of Teaching resources. See below for other related publications, lesson plans and games.

Resources
Frogs and Toads of Indiana, The Education Store, Purdue Extension
Salamanders of Indiana, The Education Store
Snakes and Lizards of Indiana, The Education Store
Turtles of Indiana, The Education Store
Help the Hellbender, Purdue Extension
Hellbender Decline, Purdue Extension-FNR Youtube
The Nature of Teaching, Lesson Plans K-12, Purdue Extension

Nick Burgmeier, Extension Wildlife Specialist & Research Biologist
Purdue University Department of Forestry and Natural Resources

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The Invasive Terrestrial Plant Rule was signed by Governor Holcomb and published on March 18, 2019. the rule goes into effect 30 days after publishing, so it will be effective in April.

The Rule States that a person must not:

• sell, offer or grow for sale, gift, barter, exchange, or distribute a species;
• transport or transfer a species;
• introduce a species

with respect to the 44 invasive plant species (see full list in the Landscape Report).

Note: Selling, offering, distributing and transporting doesn’t go into effect until April of 2020, so nurseries will have some time to sell down their stock. This is an important component of the rule to minimize economic loss to nurseries that grow and/or sell the few commercially available species that are on the list. Currently there is no mandate to eradicate existing plantings in nurseries, landscapes, or forested areas

To learn more about what an invasive species is, what damage they do, what Indiana is doing, and more please read the Landscape Report, Terrestrial Invasive Species Rule Signed by Indiana Governor.

Resources
Mile-a-Minute Invasive Vine Found Indiana, Got Nature? Blog
Invasive plants: impact on environment and people, Purdue Extension The Education Store
Invasive Plant Species in Hardwood Tree Plantations, The Education Store
Invasive Plant Species: Callery Pear, Purdue Extension The Education Store
Invasive Plant Species: Wintercreeper, Purdue Extension The Education Store
Invasive Plant Species Oriental Bittersweet, Purdue Extension The Education Store
Report Invasive Species, Purdue Invasive Species
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMaps – Early Detection and Distribution Mapping System (Report Invasives)
Cooperative Invasive Species Management Area (CISMA)
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council

Indiana Department of Natural Resources (IDNR)

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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

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Having raccoon, groundhog, or other bothersome wildlife problems? Thinking about setting traps to catch these animals? There is much to consider when using traps. Take a look at the latest publication for best results.

Wildlife specialists Brian MacGowan and Rick Shadel have collaborated to bring you this new publication: Considerations for Trapping Nuisance Wildlife with Box Traps.

Homeowners commonly set traps to capture and remove wildlife from their home or yard. Setting a box trap improperly can decrease their effectiveness and even lead to safety risks to both people and wildlife. The purpose of this publication is to 1) outline the legal and ethical factors homeowners should consider before setting a trap, 2) review the basic procedure for effectively trapping wildlife, and 3) help you to determine the fate of the captured animal.

If you have a serious, dangerous, or a nuisance wildlife issue, you may want to consider hiring a professional. Consider reading this publication before deciding whether or not you need to hire a professional: Selecting a Nuisance Wildlife Control Professional.

Resources
Preventing Wildlife Damage – Do You Need a Permit? – The Education Store, Purdue Extension resource center
Selecting a Nuisance Wildlife Control Professional, The Education Store
How to Construct a Scent Station, The Education Store
Question: How do I properly relocate raccoons from my attic?, Got Nature? Blog, Purdue Extension FNR
Nuisance Wildlife – Indiana Department of Natural Resources

Brian MacGowan, Wildlife Extensions Specialist
Purdue Forestry and Natural Resources

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