Got Nature? Blog

Purdue Landscape Report: Pollarding is a tree pruning method in which the upper branches of a tree are cut back to the same points on a regular schedule, creating a framework of knobby growth points from which new shoots emerge. The practice has been used for centuries and is especially common in landscapes where trees must be kept at a controlled height or width. Pollarding is not the same as topping, which is generally considered harmful because it removes branches without a long-term management plan. Instead, pollarding is a deliberate, repeated technique that can shape a tree into a compact, manageable form.

One of the main advantages of pollarding is size control. In urban areas, along streets, and near buildings or utility lines, trees often need to fit within tight spaces. Pollarding can reduce conflicts with overhead wires, streetlights, sidewalks, and traffic while still allowing a tree to remain in place. It can also reduce shade, which may be useful in courtyards, parking areas, and other sites where too much canopy cover is a problem. Some trees also respond by producing dense, attractive new growth, which can give them a distinctive architectural look.

Pollarding may also extend the usable life of certain trees when it is started early and maintained properly. Because the tree is kept smaller and more compact, it may be less likely to fail under wind or storm stress than a large tree with heavy limbs. In some settings, the regular cutting of new shoots can even provide a source of small-diameter wood or fodder, which helps explain why pollarding developed historically as a practical land-management method.

That said, pollarding has real drawbacks. It must be done correctly and consistently; if a tree is pollarded at the wrong age, on the wrong species, or after long neglect, the result can be stress, decay, weak regrowth, or structural problems. Not all trees tolerate the practice well, and some may decline if pollarded too aggressively. Pollarding also creates a very artificial appearance, which some people dislike. A freshly pollarded tree can look bare or severe for a time, and the repeated cuts require ongoing maintenance.

Pollarding is most strongly associated with Europe, especially Britain, France, the Netherlands, Italy, and parts of Spain, where it has a long history in both rural and urban landscapes. Today, it is still widely seen in European cities and towns, particularly on street trees and in managed public spaces. It also appears in some parts of North America, but it remains much more culturally visible and historically rooted in Europe. In many places, it is valued both for its practical function and for the distinctive form it creates over time.

Used thoughtfully, pollarding is a useful tool rather than a universal solution. It works best when matched to the right species, the right site, and a long-term maintenance plan. For the right tree in the right place, it can be both functional and visually striking.

Resources:
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Surface Root Syndrome, The Education Store, Purdue Education’s resource center
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Report INvasive, Purdue Extension
Indiana Invasive Species Council
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel (Invasive White Mulberry, Siberian Elm, Tree of Heaven)
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension YouTube Channel
Tree Selection for the “Un-natural” Environment, The Education Store
Tree Installation: Process and Practices, The Education Store
Tree Defect Identification, The Education Store
Why Is My Tree Dying?, Got Nature? Blog, Purdue Extension – FNR
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – FNR
Fifty Common Trees of Indiana
Native Trees of the Midwest, Purdue University Press
Subscribe – Purdue Extension-FNR YouTube Channel

Ben McAllister, Urban Forestry Specialist
Forestry & Natural Resources

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Purdue Forestry & Natural Resources (FNR) Extension would like to share a timely update from the Indiana Department of Natural Resources – Division of Entomology newsletter regarding a wood-boring insect that may be encountered in hardwood logs across the state. Will Drews, Entomology staff member located in south-central Indiana (Bloomington area), recently reported activity from one of the more common round-headed borer pests found in hardwood logs: the flat-faced longhorn beetle, Graphisurus fasciatus. Will shares in the Entomology Weekly Review how to identify the borer, their habitat and if we need to be conerned.

What to Look For
On the wing recently is one of the more common round-headed borer pests I find in hardwood logs, and that is the flat-faced longhorn beetle without a common name: Graphisurus fasciatus (Photos 2 – 5).  This longhorn beetle (in the family Cerambycidae) is quite large as far as longhorn beetles go, reaching up to 0.6 inches in length, and features two long antennae (aka “horns”) characteristic of most of its family (Photo 3).

Host Trees and Habitat
As a larva, Graphisurus fasciatus feeds on a variety of hardwoods and is reported to feed on pine trees as well. I generally find G. fasciatus larvae feeding between
the bark and sapwood of black walnut (Juglans nigra), white oak (Quercus alba ) and red oak (Quercus rubra) logs (Photo 6).

Identification Tips
There are several ways to differentiate this species from the less common but closely related Graphisurus despectus, but one of the surest ways is to examine the scutellum (aka the small shield-like plate at the top/between the elytra [wing covers]). In G. fasciatus, the scutellum has two small whitish patches of hair, not present on G. despectus (Photo 7). Another diagnostic characteristic of G. fasciatus is that it has elytra with emarginate (or notched) tips (Photo 8).

Should You Be Concerned?
This species can be alarming by its noticeable size and relative abundance but is not necessarily a major pest of concern as it does not usually bore into the sapwood and cause defects to the wood.

Stay Informed
FNR Extension encourages landowners and natural resource professionals to remain observant when working with hardwood logs and report unusual insect activity when found.

To stay up to date on forest health and insect alerts, consider subscribing to the  Indiana Department of Natural Resources – Entomology Weekly Review for regular updates on insects affecting Indiana’s forests and natural areas.

Will Drews, Nursery Inspector & Compliance Officer
Indiana Department of Natural Resources
Division of Entomology & Plant Pathology 

Resources:
Spotted Lanternfly, Indiana Department of Natural Resources Entomology
Box Tree Moth Range is Expanding, Purdue Landscape Report
Beetle that attacks Tree-of-Heaven found in Indiana, Purdue Landscape Report, Got Nature? Blog, Purdue Extension – FNR
Sawflies: Caterpillar Pests but not Caterpillars – PLR, Got Nature? Blog, Purdue Extension – FNR
Prepared for Insects Waking Up? – PLR, Got Nature? Blog, Purdue Extension – FNR
Case Study: Maple Tree Pests – PLR, Got Nature? Blog, Purdue Extension – FNR
Invasive Species, Purdue Extension – FNR YouTube Playlist (Asian Bush Honeysuckle, Burning Bush, Callery Pear, Multiflora rose)
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension – FNR
Finding help from a professional forester, Indiana Forestry & Woodland Owners Association
Find an Arborist video, Trees are Good, International Society of Arboriculture (ISA)

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Agricultural & Natural Resources (ANR) Newsletter: On May 5, Natural Resources professionals gathered at the Davis Purdue Agricultural Center (DPAC) in Farmland, Indiana, for a forestry and wildlife management training led by Purdue Forestry and Natural Resources’ Brian MacGowan, wildlife extension specialist and extension coordinator; Don Carlson, forester; Jarred Brooke, wildlife extension specialist; and Jessica Outcalt, natural resources training specialist. The program combined classroom updates with field-based learning focused on active land stewardship, habitat management and conservation planning.

During the field tour of DPAC and Herrmann Properties, participants explored topics including native warm-season grass management using prescribed fire, Sericea lespedeza control in native grass plantings, prairie restoration, young forest management, and oak forest management for multiple objectives. Don Carlson discussed the history and management goals of DPAC, emphasizing how tree spacing, mowing and the use of crop and nurse trees influence tree establishment and growth. Jarred Brooke highlighted challenges such as rabbit damage to young trees and invasive species management. Participants learned key wildlife habitat principles, including a practical guideline for quail habitat: If a baseball tossed into the grass rolls, the habitat structure is suitable for quail; if it does not roll, the vegetation is too dense. The day concluded with updates on the NR Training Hub, prescribed fire and evaluation efforts.

If you’re interested in bringing a program like this to your area, we’d love to hear from you, submit a request at fnrextension@purdue.edu.

Emily Kring, Extension Educator
Agriculture & Natural Resources, Purdue Extension Jay County

Jessica Outcalt, Natural Resources Training Specialist
Purdue Extension – Forestry & Natural Resources

Resources:
Natural Resources Training Hub
Explore the Rich World of Oaks with Purdue FNR Extension & Partners
Forestry for the Birds Pocket Guide, The Nature Conservancy
Natural Resources Conservation Service (NRCS)
Community Planning for Agriculture and Natural Resources: A Guide for Local Government, The Education Store, Purdue Extension’s research center
The Nature of Teaching
Help the Hellbender
Let the Sun Shine in Indiana
Community Development, Purdue Extension
Subscribe – Purdue Extension-FNR YouTube Channel, find natural resources and much more in playlists.

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Most of us have probably heard or seen a lot about pollinators in the media recently. The reason why is that pollinators are really, really important. We simply can’t live without them. Researchers estimate that one out of every three bites of food we eat is made possible by pollinators. More than 100 food crops in the U.S. depend on pollinators, including almost all fruit and grain crops.

There are many different types of pollinators including native bees, butterflies and moths, beetles, flies, wasps, and of course hummingbirds. But perhaps one of the more interesting pollinators is the Monarch. Millions of Monarchs congregate in a relative small area in Mexico each winter. In March they start their journey north which has occurred over several generations. Unfortunately, the number of Monarchs counted in overwintering colonies has declined over the past 25 years.

In response, many states including Indiana have developed a state Monarch Conservation Plan. With input from many stakeholders over several years, the Indiana Monarch Conservation Plan was released in December 2020. One goal of the plan was to create an online resource that would act as a clearinghouse for Indiana monarch and pollinator conservation data, research, best management practices (BMPs), and events. I invite you to visit the Indiana Monarch and Pollinator Conservation Hub at indianawildlife.org/monarchs.

You might be asking yourself, ‘Why is a wildlife specialist writing about pollinators?’ It turns out that quality habitat for wildlife is often quality habitat for pollinators. The diversity of wildflowers, along with the structure provided by native grasslands, trees, and shrubs, benefits all of them. Native grasslands that have a diverse mixture of wildflowers provide food, bare ground, and structure desirable for a wide variety of pollinators.

Resources
Protecting Pollinators: Why Should We Care About Pollinators?, The Education Store, Purdue Extension resource center
Ask The Expert: What’s Buzzing or Not Buzzing About Pollinators , Purdue Extension – Forestry & Natural Resources (FNR) YouTube Channel
Purdue Pollinator Protection publication series, Purdue Extension Entomology
Is My Urban Garden Helping Native Pollinators?, Purdue Landscape Report
Indiana Monarch & Pollinator Conservation Hub, Indiana Wildlife Federation
Monarch Watch, University of Kansas
100 Plants to Feed the Monarch/Other Resources Available, Xerxes Society for Invertebrate Conservation

Brian MacGowan, Wildlife Extension Specialist & Extension Coordinator
Purdue Department of Forestry and Natural Resources

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Spotted lanternfly (SLF) is a major pest of concern across most of the United States. Spotted lanternfly (SLF) is an invasive planthopper native to China that was first detected in the United States in Pennsylvania in 2014. SLF feeds on over 70+ plant species including fruit, ornamental and woody trees with tree-of-heaven as its preferred host. Spotted lanternfly is a hitchhiker and can easily be moved long distances through human assisted movement.

Know the Primary Host: Tree -of-Heaven
Tree of heaven (TOH) is the preferred host for the spotted lanternfly (SLF).  The ability to identify TOH will be critical to monitoring the spread of this invasive pest as the 4th-stage nymphs and adult spotted lantern-flies show a strong preference for TOH.

Report a Sighting
If you suspect you’ve seen a spotted lanternfly, please take the following steps:

• Take a picture and note your location.
• If you can, collect a sample of the insect by catching it and placing it in a freezer. You can use any container available as long as it has a tight seal (like a water bottle) so that the spotted lanternfly can’t escape.
• Report your sighting through one of the following channels:
  Email: DEPP@dnr.in.gov
  Online: eddmaps.org or ReportINvasive
  Phone: 1-866-663-9684

Help Stop the Spread
Everyone can play a role in slowing the spread of spotted lanternfly:

• Inspect vehicles, trailers and outdoor equipment for spotted lanternfly eggs, nymphs, and adults before driving or moving to a new location.
• Avoid moving firewood, as it can transport SLF and other invasive pests.
• Stay informed by subscribing to trusted resources like the up to date with the latest newsletters: Purdue Landscape Report and Indiana Department of Natural Resources – Entomology & Plant Pathology Weekly Review E-newsletter.
• Follow updates and management tips on social media by connecting with ReportINvasive on Facebook (@reportINvasive) and Indiana Department of Natural Resources, which shared information acrossa Facebook, Twitter and Instagram (@INdnrinvasive).

Spread Awareness
Share your spotted lanternfly knowledge with others! Share about SLF with neighbors, colleagues and your communit to help protect Indiana’s natural and agricultural resources.

Resources:
Spotted Lanternfly, Indiana Department of Natural Resources Entomology
Prepare to Manage Spotted Lanternfly, Purdue Landscape Report
Spotted Lanternfly is on the Move!, Purdue Landscape Report
Spotted Lanternfly Egg Hatch is Here, Purdue Landscape Report
Spotted Lanternfly Found in Indiana, Purdue Landscape Report
Invasive plants: impact on environment and people, The Education Store, Purdue Extension’s resource center
Woodland Management Moment: Invasive Species Control Process, Video, Purdue Extension – Forestry and Natural Resources YouTube Channel
Invasive Species, Playlist, Purdue Extension – FNR YouTube Channel
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Report Invasive

Diana Evans, Extension and Web Communication Specialist
Purdue University Department of Forestry and Natural Resources

Purdue Extension – Entomology

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One of the most dangerous pests of trees is humans, especially humans with equipment. Lawn mowers and weed trimmers can cause injuries that create a hazard when an injury leads to tree disease or death. This blog explains why the damage is so dangerous and suggests ways to protect your trees.

Defended by Bark
The site of injury is usually the root flare: the area where the tree meets the turf and gets in the path of the mower or trimmer. The root flare, like the rest of the trunk, is protected by bark, which guards a very important plant transport system just behind the woody bark layer. Specialized tubes move nutrients and water between the roots and leaves to keep the tree alive. Any damage to this transport system can affect tree health and the tree could die.

The bark layer can vary in thickness on different tree species. It can be more than an inch in thickness or less than 1/16 of an inch on young, smooth-barked trees such as maples and birches. This isn’t much protection against string trimmers and mowing equipment, especially on young, newly planted trees.

Damage Done
Any damage to or removal of the bark and the transport system can cause problems for a tree. Even when a tree tries to recover from a wound, leaves and branches often decline and die back, because food and water pathways were destroyed. Although a large wound is generally more serious than a smaller one, repetitive wounding adds up to greater trouble for the tree. If the damage extends completely around the base of the tree (a situation called girdling), the tree ultimately dies.

All tree wounds are serious when it comes to tree health. No matter what size the wound is, the damage done is irreversible. The tree must devote a great deal of energy and many resources into trying to seal off the damaged area to prevent further complications. The wounded area is an opening for wood-rotting organisms and decay fungi to enter and cause further damage. These microorganisms often attack the injured bark and invade adjacent healthy tissue, greatly enlarging the wound and extending the damage. Trees can be completely girdled from pathogen attack following injuries.

Fungi that are active on the wound surface can also deteriorate the structure of the woody tissues beneath, decaying and weakening the tree. This weakened, structurally unsound tree may eventually die and become a hazard to people around it.

Preventing Problems
Newly planted, young trees need our help to become established in the landscape. They are the trees most commonly and seriously affected by maintenance equipment.

However, injury to these trees can be avoided easily and at very low cost if you follow one or more of these suggestions.

1. Physically remove turf or prevent grass and weeds from growing at the base of the tree. This lowtech solution can eliminate a potentially serious problem.
2. Spray herbicides to eliminate vegetation around the base of the tree to decrease mowing maintenance costs. Be sure to use care when applying herbicides around trees. Carefully follow label directions.
3. Add a mulch ring, when possible, to help reduce the competition for water and nutrients. Mulch or other ground coverings reduce mowing requirements in the landscape.
4. Add a 2˝ to 3˝ layer of mulch on the root zone of the tree to provide an attractive and healthy environment for the tree to grow. This also provides a visual cue to keep equipment away from the tree.
5. Add trunk guards or similar devices to give the tree additional protection. White, expanding tree guards can help help trees withstand equipment contact and also can help to reduce winter injury.

Trees are a valuable asset to your property and are important to our environment. Every tree contributes to the urban forest and improves air and water quality in your neighborhood. Protect and preserve these growing assets by keeping mowing and weed-trimming equipment away from tree trunks. The damage lasts and it cannot be undone. Don’t create a hazard!

Resources:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Tree Defect Identification, The Education Store, Purdue Education’s resource center
Why Is My Tree Dying?, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources (FNR)
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – FNR
Surface Root Syndrome, The Education Store
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Trees and Storms: Understanding Damage, Risk and Recovery – Got Nature? Blog, Purdue Extension – FNR
Report INvasive, Purdue Extension
Indiana Invasive Species Council
ID That Tree, Playlist, Purdue Extension – FNR YouTube Channel (Invasive White Mulberry, Siberian Elm, Tree of Heaven)
Fifty Common Trees of Indiana
Native Trees of the Midwest, Purdue University Press
Subscribe – Purdue Extension-FNR YouTube Channel

Lindsey Purcell, Executive Director
Indiana Arborist Association

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Spring is one of the best times to identify trees and shrubs in Indiana. As buds break and flowers emerge, many species reveal distinctive traits that make identification easier and more enjoyable. In this collection of ID That Tree videos, Purdue Extension Forester Lenny Farlee highlights a variety of native trees and shrubs from eye-catching flowering species to lesser-known woodland plants. Whether you’re a student, landowner or simply enjoy exploring the outdoors, these videos offer a quick and accessible way to build your tree identification skills this spring.

Explore the Spring Bloom Edition videos, starting with Umbrella Magnolia:

 

Continue building your identification skills with these additional ID That Tree: Spring Bloom Edition videos:

Trees:

• ID That Tree Spring Bloom Edition: American Plum
• ID That Tree Spring Bloom: Flowering Dogwood
• ID That Tree Spring Bloom: Ohio Buckeye
• ID That Tree Spring Bloom: PawPaw
• ID That Tree Spring Bloom: Redbud
• ID That Tree Spring Bloom: Sassafras
• ID That Tree Spring Bloom: Serviceberry
• ID That Tree Spring Bloom: Yellowwood

Shrubs & Small Trees:

• ID That Tree Spring Bloom: American Hazelnut
• ID That Tree Spring Bloom: Bladdernut
• ID That Tree Spring Bloom: Blackhaw
• ID That Tree Spring Bloom: Hawthorn
• ID That Tree Spring Bloom: Mapleleaf Viburnum
• ID That Tree Spring Bloom: Spicebush in Flower

Check out more spring Got Nature? blog posts:
As the Spring Wildlflowers Emerge, so do the Woodland Invaders
Spring Tree Preparations
Spring Season is Mole Season
Question: Anything I Can Do About An Increase Of Snakes Around The House This Spring?
Protecting Spring Plants From Wildlife Damage Using Repellents
It’s Timberdoodle Time!
Putting a Little Wildlife in Your Backyard this Spring, publication in The Education Store, Purdue Extension’s resource center

If you have any questions regarding wildlife, trees, forest management, wood products, natural resource planning or other natural resource topics, Purdue Extension – FNR is here to help. Visit our Ask an Expert  webpage to connect with a Purdue Extension specialist.

Resources:
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources (FNR> Youtube Channel
A Woodland Management Moment, Playlist, Purdue Extension – FNR Youtube Channel
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
New Tool for Helping Landowners to Help Declining Birds, Forestry for the Birds, Got Nature? Blog, Purdue Extension – FNR
Native Trees of the Midwest, Purdue University Press
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
Purdue Arboretum Explorer
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR YouTube Channel
Fifty Common Trees of Indiana, Purdue Extension – FNR
ReportINvasive, Purdue College of Agriculture – Entomology
Cooperative Invasive Species Management Area (CISMA)
Report Invasive, Purdue College of Agriculture – Entomology
Professional Forester, Indiana Forestry Woodland Owners Association (IFWOA)
District Forester, Indiana Department of Natural Resources, 10+ acres
Find an Arborist, International Society of Arboriculture

Diana Evans, Extension & Web Communications Specialist
Purdue University Department of Forestry and Natural Resources

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

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Trees provide many benefits for our homes, businesses and properties. If a tree is defective, however, it may become a hazard. It is important to understand that tree owners have a duty to inspect and maintain their trees. All property owners should take reasonable steps to protect themselves by involving a qualified consultant or certified arborist.

The primary responsibilities of the arborist are to assess the potential for tree failure, advise owners of the consequences of failure and recommend the proper measures to prevent and abate failures. In assessing and managing trees it is important to create a balance between the inherent risk a tree poses and the benefits provided by the tree. Risk tree management begins with these basic steps:

Reduce tree liabilities: The property owner or manager has an obligation to periodically inspect trees for unsafe conditions. Since all trees have risk associated with them, regular inspection compels the owner or manager to evaluate the amount of risk they are willing to assume. Tree risk assessment is an important part of a program to determine if a tree is structurally sound or has the potential for failure. Inspections show that the tree owner is actively managing their trees and could reduce the owner’s liability if a failure occurs.

Inspect regularly: Trees should be assessed through inspections by a qualified arborist, preferably an International Society of Arboriculture Certified Arborist. Further inspections should be conducted after major weather events. At a minimum, trees should be inspected every five years or according to the owner’s risk tolerance.

Document and maintain records: Every inspection should be recorded and kept on file for future reference. These records are important for several reasons. Past evaluations can show how a tree has changed in its health and structure over the years. Also, written assessments are beneficial in liability claims and court cases. These written evaluations could minimize liability if a failure occurs and a claim is filed against the tree owner.

Develop a site policy and care plan: Every property manager should create and implement a policy for tree risk. This includes developing a standard of care, an inspection process and mitigation of property risk. Routine care and scheduled maintenance for all trees is essential.

Mitigate tree risk: Tree owners should make every effort to reduce risk with proper pruning and health care practices. Consider all options before deciding on removal. If possible, move or remove the “target” (see definition in “Tree Risk Assessment” section). Install structural support systems where feasible. Modify site conditions to improve the environment around the tree. Risk mitigation requires a process of logical options focusing on protecting the target and preserving the tree.

Schedule tree work: While evaluating trees for risk, the inspector should note any tree maintenance needs. The inspection can determine the timing and priority of work needed. The work should be prioritized first for safety and then for tree health. Consider potential risk, activities around the tree, level of acceptable risk and the needs of the client.

Create good tree planting strategies: Identify planting needs and locations that become available as trees are removed or destroyed. Improving the health and safety of the landscape requires an understanding of management principles, such as species selection and diversity. Also consider the impact of site infrastructure, including utilities, streets and sidewalks, and choose the right tree for the right place. Select trees known to thrive under local conditions and sustainable as long-term investments in the property

Tree Risk Assessment

For a tree to be considered hazardous it must be defective either in some part or as a whole, with risk for failure and a target that is threatened. Trees are declared hazards if assessments have been completed and mitigation is required to prevent a failure from causing damage affecting the target. To understand the implications of this concept, tree owners need to know some common terms of tree risk management.

A target is people, property or activities that could be injured, damaged or disrupted by a tree failure. Tree owners must carefully assess the area around homes, playgrounds, sidewalks and parking areas. Is the target static, moveable or mobile? Consider whether people can be kept away or separated from the target area. Also, assess the target’s value and potential. Review the target zone, which is the area where the tree or a branch is likely to strike when it falls, to determine consequences of the tree’s failure. The target zone should include the areas inside a circle around the tree, which is at least as wide as the total tree height.

Risk is the combination of the likelihood of a tree failure event and the severity of the possible consequences of that event. Every tree has the potential to fail; however, only a small number of failures actually cause injury or damage. It is impossible to maintain trees free of risk. Some level of risk must be accepted by the owner.

Hazard is a likely source of harm and is identified as the tree part or parts which will affect the target zone. For example, an entire tree or a single branch could be determined as a hazard. Hazards are identified during tree assessments, and tree owners are required to take steps to minimize the risk of damage from failure.

Individual tree characteristics must be considered when conducting evaluations for defects and failure potential. Evaluations should take a systematic approach, assessing the potential for tree failure, understanding the impact of such failures and outlining a plan of action to prevent and mitigate these failures. Tree owners should fully understand the site factors and characteristics of the tree species. There are several contingencies that influence tree failure potential and risk. These include soil type and saturation, wind exposure, pest damage, poor growing conditions and poor pruning practices such as topping.

Among the characteristics to consider when conducting tree risk evaluations are:

• Defects — severity and location. Decay, cankers, cracks and other positive indicators of weakness in the roots, stems and branches may need immediate attention if a target is present.
• Species characteristics. Some tree species possess weaker wood, a susceptibility to decay, poor growth habits and potential for pests. They could be more likely to fail after wounding because of poor ability to wall off internal decay or health issues.
• Canopy size, shape and weight distribution. This is especially true in situations where a tree is exposed to windy conditions, is leaning or has a poor stem-to-canopy ratio.
• Crown architecture. Poor branching and similar characteristics can create high-risk situations in strong winds and other weather conditions.
• Plant health and vigor. This determines how a tree can overcome wounding or pest infestations.
• The overall size of the defective part. A predetermined rating system, which outlines critical thresholds, should be considered and incorporated into the tree’s risk management plan.

Tree Inspections

Assessments should include a thorough examination of each section of the tree. A systematic approach using standardized evaluation methods aids the process. Review the canopy (crown), branches and root zone to check for signs of failure. These include:

• Dead, diseased, dying or broken branches.
• Thinning or poor canopy health.
• An unstable branching pattern, overextended or weakly attached branches, or cracks in the stems.
• Cracks or decayed areas in the main trunk.
• Exposed or decayed roots, heaving of the soil, fungus growth or cracks in the soil around the root plate.

Recurrent inspections to determine tree health and condition are critical for successful risk management programs. Trees in active-use areas should be inspected annually for defects and conditions leading to failure. Inspections are necessary after storms to ensure excessive loads have not exceeded the strength of the tree and its parts. Also, be sure to note trees with a history of failures or those with problematic structure, for more frequent monitoring and inspection. A good database and archive of tree evaluations is a critical strategy in the overall risk management plan.

Resources:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Tree Defect Identification, The Education Store, Purdue Education’s resource center
Why Is My Tree Dying?, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources (FNR)
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – FNR
Surface Root Syndrome, The Education Store
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Trees and Storms: Understanding Damage, Risk and Recovery – Got Nature? Blog, Purdue Extension – FNR
Report INvasive, Purdue Extension
Indiana Invasive Species Council
ID That Tree, Playlist, Purdue Extension – FNR YouTube Channel (Invasive White Mulberry, Siberian Elm, Tree of Heaven)
Fifty Common Trees of Indiana
Native Trees of the Midwest, Purdue University Press
Subscribe – Purdue Extension-FNR YouTube Channel

Lindsey Purcell, Executive Director
Indiana Arborist Association

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The longer daylight period and the warming weather are bringing new life to woodlands. We have a community of native plants, called spring ephemerals, that grow, bloom and produce seed quickly before the tree leaves emerge and the forest understory is wrapped in shade. Several of my favorite wildflowers are in this group, including hepaticas, trilliums, bloodroot, squirrel-corn and trout lily.

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Purdue Landscape Report: Each of us utilize mobile devices and daily consume services that require fiber and other utility infrastructure. Necessary utility work along roadways often leaves sunken trenches, compacted soil for lawns that are uneven or stripped of vegetation. If damage is significant, check with the utility provider, as many companies have restoration policies or reimbursement options for affected homeowners. However, subcontractors and varying degrees of action by utilities can make this a frustrating process.

But a few timely steps can speed recovery and simplify the process rather than dealing with later weed overgrowth or washing overtime. Begin by removing rocks, excess gravel, and construction debris. Loosen the sides of ruts or where excess soil remains beside a trench with a rake or shovel to level out and improve water infiltration and root development. If the area has settled or ruts are present after a period of time, regrade to match the surrounding lawn and ensure proper drainage away from the roadway and sidewalks. Use extra caution when these areas are collocated with drainage or susceptible to water over wash as your work can be whisked away. In some cases, ignored sunken trenches and ruts can be back filled with highly deteriorated mulch to help bring back life to the soil if one has patience to let time continue to run its course and seed later into the mellowed, high organic matter soil.

Next, incorporate quality topsoil or compost to rebuild soil structure and fertility.

Choose a grass seed mix appropriate for your region and light conditions and apply it evenly over the prepared area. Lightly rake the seed into the soil and cover with straw mulch to reduce erosion and conserve moisture. Keep the area consistently moist with light, frequent watering until seedlings are well established, typically 2–3 weeks depending on weather. If the season is not fit for seeding grass (i.e. July) try seeding a temporary cover crop like buckwheat that will attract pollinators and give short term cover while choking out weeds.

For larger or highly visible areas, sod can provide an instant fix, though it is both expensive and requires careful watering to root successfully. Once new grass reaches 3–4 inches, begin mowing and apply a light fertilizer application to encourage growth.

In summary, it depends on the time frame and the urgency you have to fix a recently created problem based on its location. For problem areas that have existed over time where weed growth has already occurred, using composted mulch to fill sunken trenches or ruts may be the easiest, while using mowing to manage weeds during summer and seed after lighly working surface more towards late summer or early fall.

View the original article on the Purdue Landscape Report website: Roadside Rehab: Rebuilding Soil and Cover After Utility Damage.

Subscribe and receive the newsletter: Purdue Landscape Report Newsletter.

Resources:
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Trees and Storms: Understanding Damage, Risk and Recovery – Got Nature? Blog, Purdue Extension – FNR
Caring for storm-damaged trees/How to Acidify Soil in the Yard – In the Grow, Purdue Extension
Why Is My Tree Dying? – Got Nature? Blog, Purdue Extension – Forestry and Natural Resources (FNR)
Tree Risk Management – Got Nature? Blog, Purdue Extension – FNR
Mechanical Damage to Trees: Mowing and Maintenance Equipment – Got Nature? Blog, Purdue Extension – FNR
Trees and Electric Lines – The Education Store
Tree Defect Identification, The Education Store
Planting Your Tree Part 1: Choosing Your Tree, video, Purdue Extension – FNR YouTube Channel
Tree Installation, The Education Store
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – FNR
Ask an Expert: Tree Selection and Planting, Purdue Extension – FNR YouTube Channel
Tree Pruning Essentials, Purdue Extension – FNR YouTube Channel
Subscribe – Purdue Extension-FNR YouTube Channel

Mark Evans, Extension Educator/Plant & Soil Science, Elkhart County
Purdue Extension – Agriculture & Natural Resources (ANR)

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