Got Nature? Blog

Question:
Are these pretty green flower shaped growth spots lichens? It just appeared on my tree this year. With this type of fungus should I be worried that it could damage the tree?

Answer:
Lichen is common on trees and not bad either. Those grayish-green patches, come in all sizes and shapes and sometimes covering much of the tree, are not feeding on your woody plants. Lichens grow on the surface of the tree, and do not penetrate any tissue. Instead, they make use of the trunk or branches for support. They can be aesthetically pleasing for many. Lichens play a very significant role as a bio-indicator. They only grow where the air quality is good and have a favorable growing environment. They help filter the air as well… so, don’t worry, be happy!

Resources:
Lichens, Purdue Botany & Plant Pathology
Purdue Plant & Pest Diagnostic Lab, Purdue Botany & Plant Pathology
Diseases of Landscape Plants: Leaf Diseases, The Education Store, Purdue Extension resource center
Surface Root Syndrome, The Education Store
Tree Installation: Process and Practices, The Education Store
Purdue Landscape Report, Purdue University

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources

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Hummingbirds are a popular attraction in any backyard. The ruby-throated hummingbird is the only species of hummingbird that nests in the Hoosier state. These colorful visitors are migratory and arrive from their wintering grounds around mid-April. So now is the time to place the hummingbird feeders.

Watch this short video to see how easy it is to make and fill your hummingbird feeder along with resources showing when and where they migrate.

Resources
Attracting Hummingbirds to Your Yard (pdf), The Education Store-Purdue Extension
Preventing Wildlife Damage – Do You Need a Permit?, The Education Store, Purdue Extension resource center
Managing Woodlands for Birds, The Education Store
Selecting a Nuisance Wildlife Control Professional, The Education Store
How to Construct a Scent Station, The Education Store
Question: How do I properly relocate raccoons from my attic?, Got Nature? Blog, Purdue Extension FNR
Birds and Residential Window Strikes: Tips for Prevention, The Education Store
Nuisance Wildlife, Indiana Department of Natural Resources

Brian MacGowan, Wildlife Extension Specialist
Purdue Forestry and Natural Resources

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While our FNR Purdue Extension specialists can’t be with you in person at workshops, meetings or in the field right now, they are still here to assist you. Don’t hesitate to reach out.

Purdue Extension – Forestry and Natural Resources, purdue.edu/fnr/extension
Ask An Expert

Wendy Mayer, Communications Coordinator
Purdue University Department of Forestry and Natural Resources

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

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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.

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.

Here are some easy ways in which urban trees and woodlots contribute to making cities more environmentally sustainable and livable:

• Trees can contribute to the increase of local food and nutrition security, providing food such as fruits and nuts for wildlife and human consumption.
• Trees play an important role in increasing urban biodiversity, providing plants and animals with a proper habitat, food and protection.
• A mature tree can absorb up to 350 lbs. of CO₂ per year. As a result, trees play an important role in climate change mitigation. In cities with high levels of pollution, trees can improve air quality making cities healthier places to live in.
• Strategic placement of trees in cities can help to cool the air between 30-40^o F, thus reducing the urban “heat island” effect, helping reduce extreme heat conditions in summer weather.
• Large trees are great biological filters for urban pollutants and particulate pollution. They absorb pollutant gases (such as carbon monoxide, nitrogen oxides, ozone and Sulphur oxides) and filter fine particulates such as dust, dirt, or smoke out of the air by trapping them on leaves and bark.
• Research shows that living in close proximity of urban green spaces and having access to them, can improve physical and mental health, for example by decreasing high blood pressure and stress. Also, research indicates greatly improved neo-natal health as well. This, in turn, contributes to the well-being of urban communities.
• Mature trees regulate water flow and play a key role in preventing floods and reducing the risk of sewer overflow. Stormwater management is a crucial city infrastructure issue and trees help. A mature tree, for instance, can intercept more than 5,000 gallons of water per year and without trees, every rain would contribute floods.
• Trees also help to reduce carbon emissions by helping to conserve energy. For example, the correct placement of trees around buildings can reduce the need for air conditioning by 30 percent and reduce winter heating bills by 20-50 percent.
• Planning urban landscapes with trees can increase property value, by up to 15 percent, and attract tourism and business.

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.

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

Purdue Landscape Report

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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

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Bird migration is one of the greatest phenomena of the natural world. Birds depend on suitable habitats to rest and refuel. In this free download publication titled No Room at the Inn: Suburban Backyards and Migratory Birds, a Purdue researcher describes ways to manage your backyard to attract birds of all types, for your enjoyment and their survival. Including a list of common migratory birds in Indiana, this publication also provides a list of other suggested resources to learn more about birds and how to identify them.

Resources:
Forest Birds, Video, Purdue Extension
Birds and Residential Window Strikes: Tips for Prevention, The Education Store, Purdue Extension resource center
Managing Woodlands for Birds, video

Jessica Outcalt, Graduate Research Assistant
Department of Forestry and Natural Resources, Purdue University

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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

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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.

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
Why Leaves Change Color, The Education Store, Purdue Extension
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

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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

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Purdue Landscape Report: When was the last time you really looked at your trees?  It’s all too easy to just enjoy their cool shade and the sound of their leaves, but if you don’t know what to look for you could miss deadly diseases or dastardly demons lurking in their leaves and branches. A quick check can help you stop a problem before it kills your tree or your local forest!

National Tree Check Month is the perfect time to make sure your tree is in tip-top shape! Our checklist will help you spot early warning signs of native pests and pathogens and invasive pests like Asian longhorned beetle, spotted lanternfly, and sudden oak death. You can stop invasive pests in their tracks by reporting them if you see them.

Is your tree healthy and normal?
Start by making sure you know the type of tree you have. Is it a deciduous tree like an oak or maple? Or is it an evergreen that like a spruce or a pine? Don’t worry about exactly what species it is. It’s enough for you to have a general sense of what the tree should look like when it’s healthy.

Check the leaves

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

Check the trunk and branches

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

Now what? If you answered YES to any of the questions above, there’s a good chance something is wrong. To decide if and how you should treat or report the problem, you’ll need to have a tentative diagnosis. Luckily, there are many ways to get one!

Know the tree species? Use the Purdue Tree Doctor to get a diagnosis and a recommendation on whether treating or reporting is needed.  This app allows you to flip through photos of problem plagued leaves, branches and trunks to help you rapidly identify the problem.  If you have an invasive pest, it will guide you how to report it.

Don’t know the tree species and still need help? Reach out to local experts. We’re happy to help!

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

Confused but think something is TERRIBLY WRONG?  Contact Purdue’s Exotic Forest Pest Educator, report online, or call 1-866-NOEXOTIC.

Resources:
Trees and Storms, The Education Store, Purdue Extension’s resource center
Why Is My Tree Dying?, The Education Store
Caring for storm-damaged trees/How to Acidify Soil in the Yard, In the Grow, Purdue Extension
Tree Risk Management, The Education Store
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Installation: Process and Practices,  The Education Store
Tree Planting Part 1 & Tree Planting Part 2, videos, The Education Store

Purdue Extension – Entomology

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