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Rooted in Research, USDA Forest Service: Non-native species are increasingly shaping forests across the eastern United States. While many introduced species coexist without major disruption, some become invasive: damaging ecosystems, reducing biodiversity and impacting the economic value forests provide. Over the past decade, the extent of forest land affected by invasive species has continued to grow, making management more complex and costly.

To address these challenges, the USDA Forest Service Research and Development team is hosting a six-part webinar series focused on invasive species in eastern forests. This series brings together leading scientists to share research-backed management strategies and explore the ecological and economic impacts of invasive species across the region.

These are virtual webinars that will be held on select Tuesdays and Thursdays in May. Each webinar will be ~60 minutes and start at 2:00 PM Eastern time. All events are open to anyone interested in forest health, conservation and management!

Here is the schedule for the upcoming webinars:

1. May 5 – Invasive Species in Eastern Forests: Extent, Impact, and Response
2. May 7 – Managing Invasive Plants: Understanding Rapid Adaptation and Strategies for Control 
3. May 12 – Hemlock Woolly Adelgid: Protecting Hemlocks with Silviculture and Biocontrol 
4. May 14 – Management Solutions for Emerald Ash Borer 
5. May 19 – Tracking Spongy Moth Defoliations and the Economics of Slowing the Spread 
6. May 21 – Emerging Threats: Asian Needle Ant and Beech Leaf Disease 

Participants must register for each webinar individually, visit to Research & Development Presents: Invasive Species in Eastern Forests learn more and sign up.

Forests play a critical role in supporting biodiversity, protecting water resources, and contributing to local and regional economies. As invasive species continue to spread, understanding how to manage and mitigate their impacts is more important than ever. This webinar series provides an opportunity to learn directly from experts working at the forefront of forest research.

To subscribe to the newsletter, visit Sign Up for Rooted in Research.

Learn and read more about the research done by the USDA Forest Service by exploring the Northern Research Station and Southern Research Station.

More Resources
ID That Tree, Playlist, Purdue Extension – FNR YouTube Channel
A Woodland Management Moment, Playlist, Purdue Extension – FNR YouTube Channel
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR YouTube Channel
Native Trees of the Midwest, Purdue University Press
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
Invasive Species Playlist, Playlist, Purdue Extension – FNR YouTube Channel
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council
Cooperative Invasive Species Management Area (CISMA)
Report Invasive, Purdue Extension
Episode 11 – Exploring the challenges of Invasive Species, Habitat University-Natural Resource University
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension – FNR
Invasive plants: impact on environment and people, The Education Store
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension-FNR
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature?
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer Tools & Resources – Purdue Extension Entomology

U.S. Department of Agriculture (USDA) Forest Service, Research & Development

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Question: “Have whippoorwill birds disappeared in our area?” We recently received this question from a bird enthusiast in southern Indiana who has noticed the absence of Eastern Whip-poor-wills in his area. He shared that when he was younger, Whip-poor-wills were common and their calls were regularly heard in the evenings. However, over time, sightings and calls have become rare or have seemingly disappeared altogether.

Resource Request: “As a landowner with access to a significant amount of family-owned property, I am interested in learning whether any programs exist in Indiana that focus on raising and releasing Eastern Whip-poor-wills or otherwise supporting their return to suitable habitats. I would also like to know if there are opportunities for private landowners to participate in conservation or habitat management efforts that could benefit this species in southern Indiana”.

Answer:  Your observation of the decline is accurate. Breeding bird surveys have documented a population decline in the U.S. over the past 40-50 years. The primary reasons for this is loss of forest habitat, loss of young forests, and declines in old-fields (many converted to other cover types – crops, pastures, houses). There is no raise and release programs for whip-poor-wills. In fact, these are rarely done and only in very unusual circumstances when a species faces extinction. It’s very expensive, logistically challenging or impossible, and it doesn’t work.  This is true even if we have appropriate habitat available, which we do not in many parts of its range.

The good news is that more groups and agencies are starting to pay attention and work to improve habitat for this charismatic and unique bird.  I provided a couple resources below that you may find of interest.

Check out these resources to learn more along with resources listed below:

The Birders’ Dozen Profile 9: Eastern Whip-poor-will, Indiana Woodland Steward
Antrostomus Vociferus, Eastern Whip-poor-will, Fire Effects Information System, US Forest Service Research and Development

More Resources:
Natural History – Whip-poor-will, Indiana Woodland Steward
Virtual Tour Brings Forest Management for Birds to Life, Purdue Extension – Forestry and Natural Resources (FNR) Got Nature? Blog
Breeding Bird Atlas, Indiana Department of Natural Resources
IN DNR Shares How to Keep Your Backyard Birds Healthy, Purdue Extension – FNR Got Nature? Blog
Question: Is there any risk of becoming infected with avian influenza virus by feeding backyard birds?, Purdue Extension – FNR Got Nature? Blog
Breeding Birds and Forest Management: the Hardwood Ecosystem Experiment and the Central Hardwoods Region, The Education Store, Purdue Extension resource center
Forest Birds, Purdue Extension – FNR YouTube Channel
Managing Woodlands for Birds Video, Purdue Extension – FNR YouTube Channel
The Birders’ Dozen, Profile: Baltimore Oriole, Indiana Woodland Steward
Ask An Expert, Playlist, Purdue Extension – FNR YouTube channel
Birds and Residential Window Strikes: Tips for Prevention, The Education Store
No Room at the Inn: Suburban Backyards and Migratory Birds, The Education Store
Putting a Little Wildlife in Your Backyard This Spring, The Education Store
Subscribe, Purdue Extension – FNR YouTube Channel

Dr. Brian MacGowan, Extension Wildlife Specialist & Certified Wildlife Biologist
Department of Forestry & Natural Resources, Purdue University

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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 – The Education Store
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 – The Education Store, Purdue Education’s resource center
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 – The Education Store
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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Walk through many forests in Indiana today, and you might not notice what is missing until you look up. Ash trees, once a common part of these woodlands, have rapidly disappeared due to the invasive emerald ash borer. Since its arrival in the early 2000’s, this small beetle has killed millions of ash trees across the state (Figure 1).

But what happens after ash trees are gone? Do new trees grow in their place, or do forests begin to change in unexpected ways?

To answer these questions, researchers revisited long-term forest monitoring plots across Indiana that were first established in the 1990s, before emerald ash borer was present. By comparing forest conditions before and after widespread ash mortality, we can begin to understand how these ecosystems are responding to one of the most destructive invasive forest pests in North America.

Even though young ash trees are still present in many forests, their numbers are dropping quickly (Figure 2). In some areas, ash seedlings have declined by more than 70 percent over the past decade. While a few saplings remain, very few are surviving long enough to replace the large trees that have been lost.

This suggests that ash is unlikely to return as a major component of Indiana forests anytime soon. As the remaining seeds in the soil are used up and fewer young trees survive, ash may become a much rarer species on the landscape.

As ash declines, other plant species are filling the gaps, but not always in the way we might expect.

Instead of fast-growing canopy trees taking over, many forests are becoming dominated by shade-tolerant species that thrive in low-light conditions. Native plants like spicebush and pawpaw are increasing in abundance, often forming dense layers in the understory. These species can make it difficult for other trees to establish and grow.

Sugar maple, another shade-tolerant species, remains common as seedlings but is not always successfully growing into larger trees. This creates a bottleneck where young trees are present, but few make it into the next stage of forest development.

At the same time, invasive plants are becoming more common in many forests following ash loss. Species such as bush honeysuckle and multiflora rose are increasing, especially in areas where ash trees have died.

These invasive plants can outcompete native vegetation, further limiting the ability of forests to regenerate diverse tree communities. Once established, they often persist and spread, creating additional challenges for forest management.

When large trees die, we might expect more sunlight to reach the forest floor, helping new trees grow. However, in many Indiana forests, the loss of ash is creating only small openings in the canopy rather than large gaps.

These smaller gaps favor shade-tolerant plants rather than species that need full sunlight to thrive. As a result, forests are gradually shifting toward communities dominated by shrubs and slow-growing, shade-adapted trees.

Ecologists often refer to this process as mesophication, a transition toward cooler, shadier, and more moisture-loving forest conditions. Over time, this can lead to forests that are more uniform and less diverse.

The loss of ash is more than just the disappearance of a single group of trees: it is part of a broader pattern of change driven by invasive species, altered disturbance patterns, and shifting forest conditions.

Without intervention, many forests may continue to develop dense understories dominated by a small number of species, including invasive plants. This can reduce tree diversity, limit wildlife habitat, and alter how forests function over time.

While forests are resilient and will continue to grow and change, they may look very different from those of the past.

Landowners, land managers, and the public all play a role in supporting healthy forests. Monitoring for invasive species, promoting a diversity of native trees, and managing dense understory growth can help improve forest regeneration.

As research continues, understanding how forests respond to the loss of species like ash will be critical for guiding conservation and management efforts in the years ahead.

Resources:
Emerald Ash Borer, Purdue Extension-Entomology
Emerald Ash Borer, Animal and Plant Health Inspection Service (USDA)
Emerald Ash Borer Invasion of North America: History, Biology, Ecology, Impacts, and Management, Daniel A. Herms, Deborah G. McCullough, 2014, Annual Review Entomology.
New Hope for Fighting Ash Borer, Got Nature? Purdue Extension- Forestry and Natural Resources (FNR)
Emerald Ash Borer Tools & Resources – Purdue Extension Entomology
Invasive Pest Species: Tools for Staging and Managing EAB in the Urban Forest, Got Nature? Blog, Purdue Extension – FNR
Now is the Time to Control Non-Native Bush Honeysuckle, Got Nature? Blog, Purdue Extension – FNR
What are Invasives Species and Why Should I Care?, Got Nature? Blog, Purdue Extension – FNR
ID That Tree: Invasive Multiflora Rose, Purdue Extension – FNR YouTube Channel
Invasive Species, Purdue Extension – FNR YouTube Channel
Report INvasive, Purdue Extension
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMapS, Early Detection and Distribution Mapping System
Cooperative Invasive Species Management Area (CISMA)
Find an Arborist, International Society of Arboriculture
Professional Forester, Indiana Forestry Woodland Owners Association (IFWOA)
District Forester, Indiana Department of Natural Resources, 10+ acres
Tree Planting Part 2: Planting a Tree, Purdue Extension – FNR YouTube Channel
Conservation Tree Planting: Steps to Success, Purdue Extension – FNR YouTube Channel
Hardwood Tree Improvement and Regeneration Center (HTIRC)
Tree Risk Management – Got Nature? Blog, Purdue Extension – FNR
Subscribe – Purdue Extension-FNR YouTube Channel

Thaddeus Swart, Graduate Research Assistant
Purdue Department of Forestry & Natural Resources

Faculty Advisors:
Dr. Mike Jenkins, Forestry & Natural Resources Professor
Purdue Department of Forestry & Natural Resources

Dr. Mike Suanders, Professor of Ecology and Natural Resources
Purdue Department of Forestry & Natural Resources

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“Why is my tree starting to die just after I built my house?”

This is a common question following new construction. Typically, trees don’t die immediately from construction damage. It often takes several years for the symptoms to develop. Connecting today’s dying tree to the damage of a few years ago is difficult for homeowners to recognize and diagnose. So what actually kills trees in a formerly wooded lot turned into a subdivision or home lot? The words “formerly wooded” should be a clue.

After selectively clearing all but the best trees on the building site, landscape equipment such as bulldozers, skid steer loaders and excavators begin to grade the lot surface into a level, compacted plane. Building infrastructure, such as the foundation, utilities, walks and driveways, is cut into place for the site. As the building process occurs, several things may happen, none of which is good for trees.

Soil and Root System Changes
Oftentimes, the below ground damage to trees is the most significant and most difficult to diagnose and remedy. Even minor changes to the soil grade or soil profile can produce negative responses from trees. Whether removing or adding soil around the roots of trees, extreme caution is advised.

Undisturbed soils, such as those found in a forested area, are composed of layers, or horizons. The lop layer occupies the upper 6 inches to 12 inches and is rich in nutrients and organic matter. This is the soil component usually missing in new home construction because of the grading and leveling process. The topsoil is typically removed, stockpiled or used elsewhere in random areas around the site.

Important chemical processes take place in this topsoil/root layer that enable trees to absorb essential nutrients and water. If a tree is unable to obtain these in sufficient quantities, decline and, eventually, death will occur. This is typical on construction sites because disturbed soils lack good structure and composition.

Soil consists of various sized particles depending upon type and composition: sand, silt and clay. In addition to the solid parts of the soil, plants need open spaces between the particles. It is recommended that soils should contain at least 12 percent oxygen for good root growth.

The compaction from equipment running over the soil in the leveling process forces these spaces together, leaving as little as 2 to 4 percent of the necessary oxygen in the soil. Unfortunately, once the soil is ready for the home, sidewalk and driveway, it’s no longer suitable for root growth or tree survival.

A relatively flat, compacted surface is required to build a home. This is achieved by grading the existing soil surface. Large equipment is used to level and compact the soil to get the bulk density necessary to support the home or structure. Soil conditions required to support a house and the necessary infrastructure are different from, and in sharp contrast to, the soils of the formerly wooded lot. Undisturbed soils, such as those in a forest, are pliable and easily penetrated by the roots because needed open spaces or pores in the soil are filled with life supporting oxygen and water.

The excavation and grading processes create a “hard pan” and remove the valuable topsoil, leaving the remaining topsoil to be used for leveling and covering the lot. This subsoil usually is compacted, nutrient-poor and lacking pore space for water and oxygen, and not suitable for long-lasting, healthy trees.

Soil Grade Changes
One of the most common causes of decline in trees on the construction site is raising the grade or soil level around existing trees. “Filling” graded areas on the site raises the level of soil and covers the original soil. This causes damage to tree root systems by cutting off the oxygen supply, preventing gas exchange between soil and air. In addition, an existing tree grows accustomed to a certain amount of water it receives. Cutting or filling soil around a tree disrupts normal water flow and either deprives the tree of water or creates excessive soil moisture. Trees can decline and die with as little as 1 inch of clay-type soils added to the existing grade. So changing the level of soils around a tree and allowing these fill soils to touch the tree can be fatal!

Studies have shown that fill soil over the root system greatly reduces the root system. In a short time, roots begin to decay and die back, causing overall decline in the tree and significantly increasing the risk of tree failure. Often this type of root damage doesn’t reveal itself for several years. Symptoms may be observed, such as untimely fall color or declining and dying branches in the upper and outermost parts of the tree canopy.

Physical Damage
Careless operation of equipment around trees can cause severe damage to trees and compromise their future health. Any damage to the tree trunk can create conditions that affect health and safety.

Construction equipment can injure the aboveground and below ground parts of a tree by breaking branches, tearing the bark, wounding the trunk or cutting trunk flares and roots. These injuries are permanent and can kill a tree.

Root Cutting
Excavating for foundations and other structures on the site severs the roots of those chosen trees remaining on the site. Since a majority of a tree’s root system is found in the topsoil area, these building processes can be devastating.

Research indicates that a large portion of most tree roots grow in the upper 12 inches of the soil profile and can spread laterally up to 2 to 3 times the height of the tree. For example, the root system of a 50-foot shade tree can be found in a 150-foot circle around the trunk. Therefore, digging foundations, sidewalks or driveways drastically reduces important root structures of these carefully selected trees. Reducing the root system lessens a tree’s ability to absorb the water and nutrients that are essential for growth. This root loss also places additional stress on the tree as it tries to recover by using stored carbohydrate reserves, further weakening the tree and making it more susceptible to insects and disease.

Root cutting near a tree also reduces stability and increases risk to the owner. Research indicates if 40 percent of the roots are cut, the tree becomes 40 percent less stable, making it more susceptible to windthrow.

Trunk and Crown Damage
The vascular system of a tree lies just beneath the bark in an area called the cambium layer. This includes the water and food-conducting tissue known as the xylem and phloem. Any injury to the cambium layer on the trunk and branches creates a wound disrupting the flow of the conducting tissue. If the damage is severe enough, the tree can die. The affected area on the trunk or branches takes months to years to heal. In some tree species which don’t heal well, the wound may never close. In this time, fungi and other wood-decaying organisms can enter the tree. This decay can begin spreading to other parts of the tree, causing more health issues for the tree and risk for the owner.

Construction damage causes health and survival issues for trees and creates risk issues for people and the property around them. Tree damage above and below ground creates weaknesses in the tree structure and reduces its ability to withstand storms and other weather-related events.

So, why does the tree seem to decline and die within a few years of construction?

The answer is reduced health and inability to perform critical plant functions because of direct or indirect damage to the tree or its soil environment.

For example, as normal photosynthesis occurs, trees store carbohydrates for next year’s growth. If a tree was healthy and growing before construction, functions such as processing food for energy storage were in effect for the coming year. When that process and any other critical function is interrupted by root damage and soil changes, the tree begins to use up its food reserves and becomes unable to replace them. This drastically weakens the tree and predisposes it to other issues such as insect and disease infestations. Trees unable to continue their basic processes won’t function well and the result is gradual decline, dieback and death. Protecting trees now prevents problems in the future. Preservation is critical for those who would save existing trees on a construction site.

To prevent this type of tree damage during construction also refer to Purdue Extension publication FNR-463-W, Construction and Trees: Guidelines for Protection.

Resources:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension YouTube Channel
Tree Installation: Process and Practices, The Education Store
Tree Pruning Essentials, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Drought Information​, Indiana Department of Natural Resources
Drought? Don’t forget the trees!, The Education Store
Tree Defect Identification, The Education Store
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Surface Root Syndrome, The Education Store
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Trees and Storms – The Education Store, Purdue Education’s resource center
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
An Introduction to Trees of Indiana
Native Trees of the Midwest, The Education Store
Subscribe – Purdue Extension-FNR YouTube Channel

Lindsey Purcell, Executive Director
Indiana Arborist Association

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Break up with your Bradford pear (and other invasives)! Tippecanoe County Soil and Water Conservation District is hosting an Invasive Plant Swap open to residents of Tippecanoe County. Apply to swap up to 10 invasive trees or shrubs thanks to funding from Duke Energy. Ask your neighbor if you can help them swap an invasive plant for a native!

Approved applicants will receive a native tree or shrub at the Tippecanoe County Soil and Water Conservation District Native Tree & Shrub Sale in September. We do not currently have funds to help with the costs of removing the invasive tree. All participants will be responsible for removing their invasive tree, shrub, or grass, providing proof of removal in the form of before and after pictures, picking up their native replacement, and planting their native replacement.

Applicants with city trees will work with the City Forester from Lafayette or West Lafayette on their tree removal and replacement process. Up to 10 plants can be replaced. Replacements come in 3 gallon pots. Shrubs will be approximately 2-3 feet tall and trees will be approximately 4-5 feet tall.

Please email tictaboutinvasives@gmail.com for any questions or about a specific species you would like to replace.

The 2026 application period will close August 1, 2026. Once 200 replacements have been applied for, applications will no longer be accepted.

For further information and the application, visit the event page on the Tippecanoe County SWCD website.

Resources:
Invasive Species, Playlist
Invasive Plant Species Identification, Video
Invasive plants: impact on environment and people, The Education Store, Purdue Extension resource center
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council
Invasive Species Playlist, Playlist, Purdue Extension – FNR YouTube Channel
What are Invasive Species and Why Should I Care?, Purdue Extension – Forestry & Natural Resources (FNR) Blog
Report INvasive, Purdue Extension
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMapS, Early Detection and Distribution Mapping System
Cooperative Invasive Species Management Area (CISMA)
Episode 11 – Exploring the challenges of Invasive Species, Habitat University-Natural Resource University
Emerald Ash Borer Information Network, Purdue University and Partners
What Nurseries Need to Know About the Invasive Species Regulation, The Education Store, Purdue Extension’s resource center
Invasive plants: impact on environment and people, The Education Store, Purdue Extension’s resource center
Tree Installation: Process and Practices, The Education Store
ID That Tree – Video Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Find an Arborist, International Society of Arboriculture

Tippecanoe County SWCD

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Discover the essential guide for anyone looking to plant forest trees or shrubs in Indiana. Whether you’re a first‑time landowner or an experienced conservationist, Planting Forest Trees and Shrubs in Indiana walks you through the 10 proven steps for establishing healthy, resilient plantings that thrive for generations. From choosing the right species to preparing your site, planting with confidence and ensuring long‑term success, this publication distills expert forestry knowledge into clear, practical advice. Ready to transform your landscape and leave a lasting legacy?

This publication provides an abbreviated 10-step approach to plant and establish healthy, productive forest and conservation plantings in Indiana. Successfully planting trees and shrubs involves much more than sticking the right end in the soil.

To receive the free download, visit the Purdue Extension’s resource center: The Education Store – Planting Forest Trees and Shrubs in Indiana.

Resources:
Control Management of Poison Hemlock, Got Nature? Blog, Purdue Extension – Forestry & Natural Resources (FNR)
Publication:  Invasive Plant Series-Tree of Heaven, Got Nature? Blog, Purdue Extension – FNR
Publication – Invasive Plant Series: Swallow-worts, Got Nature? Blog, Purdue Extension – FNR
Question: What is the best management process with cut invasive brush tops?, Got Nature? Blog, Purdue Extension – FNR
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Pruning Essentials, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Surface Root Syndrome, The Education Store
District Forester, Indiana Department of Natural Resources, 10+ acres
Directory of Professional Foresters, Indiana Forestry & Woodland Owners Association (IFWOA)
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
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
An Introduction to Trees of Indiana
Native Trees of the Midwest, The Education Store
Subscribe – Purdue Extension-FNR YouTube Channel

Ron Rathfon, Regional Extension Forester, Southern Indiana Purdue Agriculture Center (SIPAC)
Purdue Forestry and Natural Resources

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In this edition of ID That Tree, Purdue Extension Forester Lenny Farlee introduces us to Virgin’s Bower clematis, a native vining plant found in Indiana that’s especially noticeable when it blooms later in the growing season. Often seen climbing over nearby vegetation or spreading across open spaces, this species adds both beauty and ecological value to the landscape. Learn where Virgin’s Bower is typically found, how to recognize it and how it compares to a similar invasive look-alike. Whether you’re a student, landowner or simply curious about native vines, this video offers a quick introduction to this attractive and useful Indiana species.

 

If you have any questions regarding wildlife, trees, forest management, wood products, natural resource planning or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources:
ID That Tree – Video Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
Purdue Arboretum Explorer
Conservation Tree Planting: Steps to Success, Purdue Extension – FNR YouTube Channel
A Woodland Management Moment, Playlist, Purdue Extension – FNR YouTube Channel
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR YouTube Channel
Fifty Common Trees of Indiana, Purdue Extension – FNR
Indiana Invasive Species Council
Cooperative Invasive Species Management Area (CISMA)
Report Invasive, Purdue Extension
Habitat University, Episode 12 – Exploring the challenges of Invasive Species, Habitat University-Natural Resource University
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Native Trees of the Midwest, Purdue University Press
Professional Forester, Indiana Forestry Woodland Owners Association
District Forester, Indiana Department of Natural Resources, 10+ acres
Find an Arborist, International Society of Arboriculture
Forest Improvement Handbook, The Education Store

Lenny Farlee, Extension Forester
Hardwood Tree Improvement and Regeneration Center
Purdue Department of Forestry & Natural Resources

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