Purdue University - Extension - Forestry and Natural Resources
Purdue Landscape Report: Yes, we need trees and here’s why…
Trees have presented as more than just a pretty face as research has indicated that trees are even more valuable for their function as much as their form. Currently, more than 50 percent of the world’s population now lives in towns and cities. In the Hoosier state, the last census indicated that 72% of our population lives in an urban area and this statistic is increasing annually.

Properly planted trees improve living conditions in downtown and suburban areas. Sources
For the most part, the rapid expansion of cities takes place with little consideration to land use planning strategy. The resulting human pressure has highly damaging effects on our urban trees and green spaces. The environmental impacts of climate change are intensified by urbanization such as increased pollution, increased temperatures, and larger demands on infrastructure such as stormwater systems.
Urban trees can help to mitigate some of the negative impacts and social consequences of urban sprawl and make cities more resilient to these changes. These important functions are called ecosystem services. This is the way urban foresters measure the benefits that trees provide other than just their beauty. Ecosystems services are the many benefits that trees and plants provide to the community. They improve our quality of life by providing food, cleaner air and water, regulating temperatures, supporting pollination and providing recreational, health and spiritual benefits.

People will stay longer and enjoy urban economy more with tree-lined streets. Sources

Trees are proven to reduce length of hospital stays and improve birth outcomes. Sources

Recreational areas are critical to community well-being. Sources
Here are some easy ways in which urban trees and woodlots contribute to making cities more environmentally sustainable and livable:
These are just a few examples of the functional benefits that trees provide to our everyday life. A community or neighborhood with well-planned and well-managed green infrastructure becomes more resilient, sustainable and equitable in terms of livelihood improvement, climate change mitigation and adaptation, disaster risk reduction and ecosystems conservation. Throughout their lifetime, trees can thus provide a benefit package worth two to three times more than the investment made in planting and caring for them. Trees aren’t the answer, but they are part of the equation. Planting trees is important, but their maintenance is as equally important.

Trees make life better. Sources
For more information on urban tree care, visit the Purdue Education Store for tree care tips and suggestions.
Resources
Tree Appraisal and the Value of Trees, The Education Store, Purdue Extension’s resource center
Tree Pruning Essentials, Publication & Video, The Education Store
Tree Installation: Process and Practices, The Education Store
Tree Selection for the “Un-natural” Environment, The Education Store
The Nature of Teaching: Trees of the Midwest, The Education Store

The Purdue Extension and Illinois-Indiana Sea Grant Rainscaping Education Program was highlighted in the National Oceanic and Atmospheric Administration’s Education Accomplishments Report for fiscal year 2019.
This report highlighted all of NOAA’s greatest accomplishments related to education in five main goal areas: science informed society, conservation and stewardship, safety and preparedness, future workforce and organizational excellence.
The Rainscaping Education Program was featured in the Conservation and Stewardship section of the report. The Purdue Rainscaping Education Program offers state-wide training for Purdue Master Gardeners, conservation agencies and organizations, stormwater professionals and landscape companies and consultants. Through two-day workshop sessions, the program provides an introduction to rainscaping and rain gardens, including segments on site selection, plant selection, garden design, installation, maintenance and community engagement.
“It is wonderful to have the innovative and collaborative work of the Purdue Rainscaping Education Team recognized for its efforts,” Kara Salazar, assistant program leader and extension specialist for sustainable communities said. “The team has been working together since 2013 to develop and implement the interdisciplinary program addressing the need for community education on sustainable landscape practices to prevent polluted runoff.”
Salazar and John Orick, Purdue Master Gardener State Coordinator, are co-leads on the project. View the full Rainscaping Team.
The featured segment on the Rainscaping program from the NOAA annual report is below.

Resources
What is Rainscaping? Purdue Rainscaping Education Program Video, Purdue Extension
Q&A About Drainage Water Recycling for the Midwest, The Education Store, Purdue Extension resource center
Become a Purdue Master Gardener, The Education Store
Plan Today For Tomorrow’s Flood, The Education Store
Kara Salazar, Assistant Program Leader and Extension Specialist for Sustainable Communities
Department of Forestry and Natural Resources
Trees provide many benefits and value to property owners in functional, aesthetic, social, environmental, and even economic ways. Functional benefits include mitigating climate change by storing carbon, removing pollution from the atmosphere, managing stormwater runoff, and improving air quality. Trees provide oxygen and many other benefits – such as shade, which can impact home cooling costs.
The collective value of trees makes a difference in people’s health and quality of life in cities and towns everywhere. This updated Purdue Extension publication Tree Appraisal and the Value of Trees describes methods used to appraise trees and landscapes that can determine their value and worth, reasons why a tree should be appraised, the factors that go into tree appraisal, what appraisal ratings mean, and sample scenarios.
Resources
The Nature of Teaching: Trees of the Midwest, The Education Store, Purdue Education Resource Center
Corrective Pruning for Deciduous Trees, The Education Store
Resources and Assistance Available for Planting Hardwood Seedlings, The Education Store
Tree Support Systems, The Education Store
Purdue University, Department of Forestry and Natural Resources
Trees in the landscape are highly prized and provide many benefits to you and your home. However, those shallow roots that appear on the surface of our lawns can create real headaches, especially when trying to grow lush turfgrass. This free download Surface Root Syndrome publication will help you learn what surface roots are, common approaches to address the problem, and best practices to management.
Resources
Find an Arborist video, Trees are Good-International Society of Arboriculture (ISA)
Caring for storm-damaged trees/How to Acidify Soil in the Yard – In the Grow, Purdue Extension
Tree Appraisal and the Value of Trees, The Education Store, Purdue Extension resource center
Tree Support System, The Education Store
Why Is My Tree Dying? – Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
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
Urban Forestry Playlist, Purdue Extension-Forestry and Natural Resources YouTube Channel
Lindsey Purcell, Chapter Administrator & Master Arborist
Indiana Arborist Association
Purdue Landscape Report: There are many different aspects of tree work which include a wide range of costs, but let’s start with the most common expense: tree removal. It can be difficult to understand why removing a tree can cost so much when the whole process seems as simple as “just cutting it down.” In reality, the work is usually much more involved than making a few cuts with a chain saw and then hauling it all away.
Complexity – Trees being removed often need to be cut apart in sections to avoid dropping the whole tree or large pieces onto the lawn or landscape or into the street. This is a safer approach and also prevents serious damage to the turf and landscape below. News reports are full of accidents involving untrained tree workers, or homeowners, attempting to cut down a tree without the knowledge of how the tree reacts to being cut. Usually, specialized equipment is needed, such as aerial lifts or cranes to access the tree safely. This equipment is costly to acquire and maintain. Some of the typical equipment such as these mentioned can cost more than some homes! Often, the use of this equipment involves setting up traffic control in busy streets where permits and additional flagging support are needed.
Difficult and dangerous –
Tree pruning and tree removal, is difficult and dangerous work. Also, there is a reason why the tree is being removed. Often it has been deemed high risk or presents a danger on the site. Tree crews are regularly asked to work on trees with compromised structure from storm damage or years of neglect. These compromised trees are often dead trees, which are particularly dangerous. A tree that has been dead for several years usually becomes brittle and inflexible. When you try to cut it down, controlling the direction of fall is a challenge and it will often shatter, throwing broken branches in an uncontrolled manner. Often, tree workers are in trees that have electrical conductors running through the branches. That risky situation should speak for itself.
Insurance, Licensing – Because tree work can be hazardous, qualified companies will have expensive liability insurance to protect the homeowner’s property, as well as workers’ compensation insurance to help cover injuries sustained by the crew, should they occur. You get what you pay for and this includes tree care as well! If you select a company that is less expensive, they may not carry insurance which leaves the tree owner at a high risk of having to pay damages several times the original job estimate, if something goes wrong. Always check with your tree care company to be sure they can validate proper insurance before starting tree work. This applies to any service company which may be used in and around your home or property.
Trained and Certified Workers – Its best to choose a tree care company where the crew has current industry credentials
and a history of training and experience. How do you know if a company’s staff is trained and experienced? Ask to see their credentials and look for programs such as the International Society of Arboriculture (ISA) Certified Arborist, or the Tree Care Industry Association (TCIA) Certified Treecare Safety Professional which are indicators of a professional business with the expertise to perform the work. Tree owners and managers have the option to interview two or three tree care companies before deciding about tree removal or other critical practices such as pruning. Ask to see a copy of the current insurance certificate as well as copies of the crew’s competency credentials. If a company representative hesitates to provide these documents or insists, they don’t need to “prove” themselves, find another company to perform the work. Ask for references. This is easy since often all that is needed is to drive by a location to see the quality of the pruning work or removal work completed.

Find a professional – Also, to check for an ISA Certified Arborist in your area, visit the website www.treesaregood.org then click on the link “Find an Arborist”. By entering your zip code, a list of credentialed arborists can be found nearest your location.
Tree care performed properly will be an investment in your property that, when done correctly, will give you valued returns for decades.
Resources
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store, Purdue Extension’s resource center
Tree Appraisal and the Value of Trees, The Educational Store
Tree Pruning Essentials, video, The Education Store
Tree Pruning Essentials, The Education Store
Tree Selection for the “Un-natural” Environment, The Education Store
Lindsey Purcell, Chapter Executive Director
Indiana Arborist Association
Purdue Landscape Report: Just as sure as you try to predict the weather, it is likely to change. But going out on a limb, I predict that we will have a bit of a dud for fall color display this year. Not a very risky prediction, considering that many plants already are starting to turn color and/or drop leaves in some areas of the state.

Nyssa sylvatica (black gum) showing early fall color due to drought stress. Source
So why would the colors be early and/or a bit duller than usual? Certainly, some of the reason why plants display fall colors has to do with the genetic makeup of the plant. That doesn’t change from year to year. But the timing and intensity of fall colors do vary, depending on factors such as availability of soil moisture and plant nutrients, as well as environmental signals such as temperature, sunlight, length of day, and cool nighttime temperatures.
The droughty conditions experienced during much of the second half of summer are likely to have decreased the amount of fall color pigment. Southern Indiana has been particularly parched. Despite recent rains in some areas, much of the state remains designated as abnormally dry to moderate drought. You can check your area’s conditions at the US Drought Monitor for Indiana. Additional maps and data is available at the Midwest Regional Climate Center.
Growing conditions throughout the season affect fall color as does current weather. Colors such as orange and yellow, which we see in the fall, are actually present in the leaf all summer. However, those colors are masked by the presence of chlorophyll, the substance responsible for green color in plants during the summer. Chlorophyll allows the plant to use sunlight and carbon dioxide from the air to produce carbohydrates (sugars and starch). Trees continually replenish their supply of chlorophyll during the growing season.
As the days grow shorter and (usually) temperatures cooler, the trees use chlorophyll faster than they can replace it. The green color fades as the level of chlorophyll decreases, allowing the other colored pigments to show through. Plants that are under stress–from conditions like prolonged dry spells–often will display early fall color because they are unable to produce as much chlorophyll.
Yellow, brown and orange colors, common to such trees as birch, some maples, hickory and aspen, come from pigments called carotenoids, the same pigments that are responsible for the color of carrots, corn and bananas.
Red and purple colors common to sweet gum, dogwoods and some maples and oaks are produced by another type of pigment called anthocyanin, the pigment responsible for the color of cherries, grapes, apples and blueberries. Unlike chlorophyll and carotenoids, anthocyanins are not always present in the leaf but are produced in late summer when environmental signals occur. Anthocyanins also combine with carotenoids to produce the fiery red, orange, and bronze colors found in sumac, oaks, and dogwoods.
Red colors tend to be most intense when days are warm and sunny, but nights are cool–below 45º F. The color intensifies because more sugars are produced during warm, sunny days; cool night temperatures cause the sugars to remain in the leaves. Pigments are formed from these sugars, so the more sugar in the leaf, the more pigment, and, thus, more intense colors. Warm, rainy fall weather decreases the amount of sugar and pigment production. Warm nights cause what sugars that are made to move out of the leaves, so that leaf colors are muted.
Leaf color also can vary from tree to tree and even from one side of a tree to another. Leaves that are more exposed to the sun tend to show more red coloration while those in the shade turn yellow. Stress such as drought, poor fertility, disease or insects may cause fall color to come on earlier, but usually results in less intense coloration, too. And stress or an abrupt hard freeze can cause leaves to drop before they have a chance to change color.
So far, weather conditions lead me to think this will be one of those not so showy fall color years. I hope I am proven wrong!
Resources
Fifty Common Trees of Indiana
An Introduction to Trees of Indiana
Native Trees of the Midwest, Purdue University Press
Why Leaves Change Color, USDA Forest Service, Northeastern Area
B. Rosie Lerner, Retired Extension Consumer Horticulturist
Purdue Horticulture and Landscape Architecture
Cities and towns in the U.S. contain more than 130 million acres of forests. These forests vary extensively in size and locale. An urban forest can describe an urban park such as Central Park in New York City, NY, street trees, nature preserves, extensive gardens, or any trees collectively growing within a suburb, city, or town. Urban forestry is the name given to the care and maintenance of those ecosystem areas that remain after urbanization. Data from the 2010 census indicated more than 80% of Americans live in urban centers with a population increase greater than 12%. The population of Indiana represents only 2.1% of the nation. In the last 8 years, IN has had an influx of 200,000 people which represents a population increase of 3.0%!
Urban forests, which help filter air and water, control storm water runoff, help conserve energy and provide shade and animal habitat must be maintained. As our nation becomes more urbanized, appreciate those urban foresters working to ensure we have save urban forest spaces to enjoy. These precious resources add more than curb appeal and economic value, they improve our quality of life.
What does an urban forester do? Here’s a quick answer:
References:
Purdue Urban Forestry & Arboriculture, Purdue Forestry and Natural Resources
USDA Forest Service Urban Forests, United States Department of Agriculture
US Census Bureau, United States Census Bureau
Interested in Purdue Urban Forestry? Contact:
Lindsey Purcell, Chapter Executive Director
Indiana Arborist Association
Ben McCallister, Urban Forestry Specialist
Forestry and Natural Resources
Resources:
Tree Support Systems, The Education Store, Purdue Extension Resource Center
Corrective Pruning for Deciduous Trees, The Education Store
Tree Installation: Process and Practices, The Education Store
What plants can I landscape with in area that floods with hard rain?, Got Nature? Blog, Purdue University Forestry and Natural Resources Extension
One of the most dangerous pests to trees is a human, especially with equipment.
Injuries to trees caused by a lawn mower or weed trimmer can seriously threaten a tree’s health.
Additionally, damage to the bark layer of trees causes a long-term liability by creating a wound which leads to a defect, becoming an unsafe tree.
The site of injury is usually the root flare area, where the tree meets the turf and gets in the path of the mower or trimmer. The bark on a tree acts to protect a very important transport system called the cambium layer.

This is where specialized tubes are located which move nutrients and water between the roots and the leaves. Bark layers 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 birch trees. This isn’t much protection against string trimmers and mowing equipment, especially the young trees.
Any type of damage or removal of the bark and the transport system can result in long-term damage. Damage, which extends completely around the base of the tree called girdling, will result in ultimate death in a short time.

Tree wounds are serious when it comes to tree health. The wounded area is an opportunity for other insects and diseases to enter the tree that causes further damage. Trees can be completely killed from an attack following injuries. Fungi becomes active on the wound surface, causing structural defects from the decay. This weakens the tree or it eventually dies, creating a risk tree to people around it.
Newly planted, young trees need all the help we can provide to become established in the landscape and these trees are often the most commonly and seriously affected by maintenance equipment. However, injury can be avoided easily and at very low cost with these suggestions.
The removal of turf or prevention of grass and weeds from growing at the base of the tree are low-tech solutions to eliminate a serious problem. Spraying herbicides to eliminate vegetation around the base of the tree can decrease mowing maintenance costs. Be sure to use care when applying herbicides around trees.Trees are a major asset to your property and important to our environment. Protect our trees and preserve these valuable assets by staying away from tree trunks with any mowing or weed trimming equipment. The damage lasts and it cannot be repaired and often results in losing your tree.
Purdue University Landscape Report Article
Resources
Corrective Pruning for Deciduous Trees, The Education Store – Purdue Extension resource center
What plants can I landscape with in areas that floods with hard rain?, Purdue Got Nature? Blog
Tree support systems, The Education Store
Tree Installation: Process and Practices, The Education Store
Lindsey Purcell, Urban Forest Specialist
Forestry and Natural Resources
United States Department of Agriculture Animal and Plant Health Inspection Service Bulletin: USDA declares August Tree Check Month and urges public to look for Asian longhorned beetle.
WASHINGTON, July 23, 2019 — August is the height of summer, and it is also the best time to spot the Asian longhorned beetle (ALB) as it starts to emerge from trees. The U.S. Department of Agriculture (USDA) is asking the public to take five minutes to step outside and report any signs of this invasive pest. Checking trees for the beetle will help residents protect their own trees and better direct USDA’s efforts to eradicate this beetle from the United States.
“It’s important to look for signs of the beetle now, because it’s slow to spread during the early stages of an infestation,” said Josie Ryan, APHIS’ National Operations Manager for the ALB Eradication Program. “With the public’s help, we can target new areas where it has spread and provide a better chance of quickly containing it.”
The Asian longhorned beetle feeds on a wide variety of popular hardwood trees, including maple, birch, elm, willow, ash and poplar. It has already led to the loss of more than 180,000 trees. Active infestations are being fought in three areas of the country: Worcester County, MA, Long Island, NY (Nassau and Suffolk Counties), and Clermont County, Ohio.
“Homeowners need to know that infested trees do not recover and will eventually die, becoming safety hazards,” warned Ryan. “USDA removes infested trees as soon as possible because they can drop branches and even fall, especially during storms, and this keeps the pest from spreading to nearby healthy trees.”
The Asian longhorned beetle has distinctive markings that are easy to recognize:
After seeing signs of the beetle:
It is possible to eliminate this pest and USDA has been successfully doing so in several areas. Most recently, the agency declared Stonelick and Batavia Townships in Ohio to be free of the Asian longhorned beetle. We also eradicated the beetle from Illinois, New Jersey, Boston, MA, and parts of New York. The New York City boroughs of Brooklyn and Queens are in the final stages of eradication.
For more information about the Asian longhorned beetle, other ways to keep it from spreading—such as not moving firewood—and eradication program activities, visit USDA Animal and Plant Health Inspection Service. For local inquiries or to speak to your State Plant Health Director, call 1-866-702-9938.
Other Resources:
Report Invasive Species, Purdue Agriculture & Indiana Invasive Species Council
Great Lakes Early Detection Network, Bugwood Apps
New Hope for Fighting Ash Borer, Got Nature? Blog
Mile-a-Minute Invasive Vine Found Indiana, Got Nature? Blog
Sericea Lespedeza: Plague on the Prairie, Got Nature? Blog
Invasive Plants: Impact on Environment and People, The Education Store, Purdue Extension
Invasive Plant Species in Hardwood Tree Plantations, The Education Store
Invasive Plant Species: Callery Pear, Purdue Extension The Education Store
United States Department of Agriculture Animal and Plant Health Inspection Service
Purdue Landscape Report: When was the last time you really looked at your trees? It’s all too easy to just
enjoy their cool shade and the sound of their leaves, but if you don’t know what to look for you could miss deadly diseases or dastardly demons lurking in their leaves and branches. A quick check can help you stop a problem before it kills your tree or your local forest!
National Tree Check Month is the perfect time to make sure your tree is in tip-top shape! Our checklist will help you spot early warning signs of native pests and pathogens and invasive pests like Asian longhorned beetle, spotted lanternfly, and sudden oak death. You can stop invasive pests in their tracks by reporting them if you see them.
Is your tree healthy and normal?
Start by making sure you know the type of tree you have. Is it a deciduous tree like an oak or maple? Or is it an evergreen that like a spruce or a pine? Don’t worry about exactly what species it is. It’s enough for you to have a general sense of what the tree should look like when it’s healthy.
Check the leaves
Check the trunk and branches
Now what? If you answered YES to any of the questions above, there’s a good chance something is wrong. To decide if and how you should treat or report the problem, you’ll need to have a tentative diagnosis. Luckily, there are many ways to get one!
Know the tree species? Use the Purdue Tree Doctor to get a diagnosis and a recommendation on whether treating or reporting is needed. This app allows you to flip through photos of problem plagued leaves, branches and trunks to help you rapidly identify the problem. If you have an invasive pest, it will guide you how to report it.
Don’t know the tree species and still need help? Reach out to local experts. We’re happy to help!
Confused but think something is TERRIBLY WRONG? Contact Purdue’s Exotic Forest Pest Educator, report online, or call 1-866-NOEXOTIC.
Resources:
Trees and Storms: 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