Got Nature? Blog

Purdue Landscape Report: Finally, spring has sprung and summer is on its way. The hot days and warm nights are welcome for us, but summer isn’t always so kind to our trees, especially in our urban forests and landscapes. Trees are dynamic living organisms that respond to external stimuli in very strategic ways and each season presents its own challenges and summer is no different.

During the summer, growth slows as some resources become limited and typically, this is water. As the summer season progresses, the likelihood of less rain means potential drought conditions. The primary responses of a tree to heat and drought are a reduction in photosynthesis and carbon assimilation rates. This translates to a reduction in energy production and food reserves. This reduction can increase vulnerability to health issues and reduced defense mechanisms against pests.

There are some key steps to summer tree care which can help trees through potentially challenging conditions in the summer.

1. Watch the water; be sure to supplement trees with additional watering when there isn’t adequate rainfall that measures at least an inch per week. Mature trees need supplemental watering just as the younger, newly established trees. Be sure to know the symptoms of dry conditions and how much to water with more information here.
   

   Drought symptoms should be monitored weekly to prevent decline and dieback during the dry months.

2. Refresh your mulch; adding mulch to tree rings or even better, expanding them is a great way to reduce water requirements and competition for water and other resources. As trees grow, so do the roots under the tree and expanding mulching rings outward to the dripline of the crown is a great way to keep trees healthier. Also, this helps with those surface root issues as well.
   

   Expanding mulch rings is a great way to improve tree root health and reduce surface root issues.

3. Don’t get bugged too much; summer brings out the best in pests too! Many mite and scale species love the heat and can cause major damage and even death to your trees. Look for signs and symptoms of scale infestations and mite damage on your trees and shrubs now. More information on scales can be found here.  Additional details on mite damage can be found here.
4. A nip and tuck are fine; summer is actually a good time to prune as needed to meet objectives such as reducing risk, improving branch structure, and removing conflicts or improving aesthetics. Be sure to only remove what is necessary and reduce the amount of live, green tissue removal. Remember, this is what produces food for the tree. Additional tree pruning techniques are discussed in this publication.
   

   Proper pruning during the summer is a good way to improve aesthetics and stability during stormy weather.

5. Call in a professional; it is always a good idea to consult an ISA Certified Arborist for answers to tree questions. A reputable arborist trained in best practices and current research can provide the best solutions to keeping trees healthy and reduce potential risk for damage during those summer storms. Finding a qualified arborist can be a challenge itself. Refer to this website to find an ISA arborist near you.

For additional information on urban tree care, check out all the publications at the Purdue Education Store.

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 Selection for the “Un-natural” Environment, The Education Store, Purdue Extension resource center
Tree Installation: Process and Practices, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
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
Purdue Landscape Report

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

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Purdue Landscape Report: Pruning is an important maintenance practice on trees that is discussed a great deal. An essential part of making the pruning cut properly is the ability to identify the parts of a branch. Identification of the branch bark ridge and branch collar are vital to severing the branch in a place that facilitates fast and effective wound closure, reducing decay in the location of the cut.

Branches on trees arise from lateral buds present in leaf axils. Initially, lateral shoots (branches) grow in length and diameter at approximately the same rate as the parent stem. As branches become shaded naturally by crown expansion, photosynthesis is reduced in that location and growth slows to a lesser rate than the parent or main stem. A swollen area or collar develops at the junction of branch and stem because of their differential growth rates and by the intermingling of vascular tissues from both the branch and the stem or trunk.

This swollen area is commonly referred to as a branch collar and often present in many branches on the underside of the branch. This specialized location on the branch is composed of trunk (parent stem) wood. The branch collar contains a protective chemical zone that inhibits the movement of decay organisms from dead or dying branches into healthy tissues of the parent stem. As branches begin to die from shading, pests or storm damage, for examples, they usually are walled off (compartmentalized) by tissues in the branch collar which prevents movement of decay organisms into the parent stem.

Another important branch component to identify in tree branches is the branch bark ridge. This part of the attachment is composed of rough, usually darkened, raised bark formed at the union where the branch meets the parent stem. The ridge extends from the top of the branch down both sides of the branch union. Together with the branch collar, the portion of the ridge pushed up in the union provides our target for the pruning cut. The BBR is present on every branch union and is an important identifying feature for determining tool placement.

The combination of the branch collar, branch bark ridge, and the overlap between the branch and stem are the branch components that form what is called the branch protection zone. This zone contains specialized chemical compounds that help resist the spread of disease in the tree and facilitate wound-sealing. Always avoid damaging the area within the branch collar and branch bark ridge to help the tree recover from the pruning cut as quickly as possible.

For the best advice on tree maintenance and care, seek out a tree care professional with the experience and expertise to care for your trees. Search for a tree care provider in your area. Also, consider hiring an ISA Certified Arborist which can be found here.

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 Selection for the “Un-natural” Environment, The Education Store, Purdue Extension resource center
Tree Installation: Process and Practices, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Purdue Landscape Report

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

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Question: My hackberry trees are dropping leaves for no apparent reason. The leaves look fine, no bugs or mold spots or discoloration of any kind. Do you have any idea what might be causing the leaf drop?

Answer: The loss of leaves on hackberries in spring is an occasional phenomenon in the Midwest. The exact cause has never been determined. In past years, no association was found between the leaf drop and insects or diseases. The most popular theory is that cold spring temperatures may have damaged the leaf buds or newly developing leaves, causing the leaf drop. Remember that blast of winter in April!? It’s likely the loss of leaves in spring is temporary. In past years, affected hackberries quickly developed new leaves and recovered completely. Just be patient and wait for the reflush of growth.

Leaves may be falling from your maple trees right now. This is a common spring issue caused by the maple petiole borer. Look closely at the fallen leaves for abnormally short petioles and examine the tree canopy for broken petioles that have remained attached. Although sugar maples are generally preferred, other maples may occasionally be infested. Fortunately, while the leaf drop may appear dramatic, the actual impact on the overall health of affected trees is minimal, so controls are not necessary. Also, a re-flush of leaves may be expected.

Resources:
Will My Tree Recover After Losing Their Leaves, Purdue Landscape Report
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Planting Your Tree Part 2: Planting A Tree, Purdue Extension YouTube Channel
Tree Installation: Process and Practices, The Extension Store, Purdue Extension resource center
Ask an Expert: Tree Selection and Planting, Purdue FNR Extension YouTube Channel
Find a Certified Arborist, International Society of Arboriculture (ISA)-Trees Are Good

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

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Question: We live near the Amazon Fulfillment Center in the Jeffersonville/Charlestown area. We have significant wind most days. We planted a dogwood tree in our front yard 2 years ago. It struggled through last spring and this year half is not going to make it. Is there a better, preferred tree for this area that we might choose to replace it? We prefer a short stature tree vs one that may reach 20 to 30 feet.

Answer: Dogwood trees can be a challenge to sustain in the landscape due to its environmental requirements. Cornus florida is a “woods edge” tree that like moist, well-drained soil. Most importantly, these trees require protection and at least partial shade to guard against the wind and sun. Recommended publication: Tree Selection, Tree Installation.

Resources
Tree Selection, The Education Store, Purdue Extension resource center
Ask an Expert: Tree Selection and Planting, Purdue Extension –  FNR YouTube Channel
Tree Installation, The Education Store
Tree Pruning Essentials, Publication & Video The Education Store
Tree Selection, Tree Installation & Tree Pruning for Landscape, Webinars, Purdue Extension – Forestry and Natural Resources YouTube channel
Planting Problems: Trees Planted Too Deep, Purdue Extension – FNR YouTube Channel
ID That Tree, Purdue Extension – FNR Playlist

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

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Spring is here! It is the time of year for some of us to be planting new trees. In this Ask an Expert session, we welcome Lindsey Purcell, urban forestry specialist, as he teaches us how to plant and properly care for our trees. He goes over the tree selection process, including which invasive species trees we should avoid, and how to continue to take care of our trees once planted.

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:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension – Forestry and Natural Resources YouTube Channel
Indiana Invasive Plant List, Indiana Invasive Species Council, Purdue Entomology
Alternatives to Burning Bush for Fall Color, Purdue Landscape Report
Invasive Plant Species: Callery Pear, Youtube, Purdue Extension
Equipment Damage to Trees, Purdue FNR Extension
Landscape Report Shares Importance of Soil Testing, Purdue FNR Extension

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

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Join Lenny Farlee, Purdue FNR Extension Forester, as he explains why the typical thinking of what is a tree and what is a shrub isn’t always simple as far as looking for the “single” trunk to call it a tree. There is some crossover. Lenny shares the different ways to identify if it is a shrub and then the various species in Indiana.

 

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:
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Native Trees of the Midwest, Purdue University Press
101 Trees in Indiana, Amazon
ID That Tree, Purdue Extension – Forestry and Natural Resources YouTube Playlist

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

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Join Lenny Farlee, Purdue FNR Extension Forester, as he goes over the different principles used to identify various trees in Indiana. Lenny will provide examples of species to practice using those principles for identification.

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:
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Native Trees of the Midwest, Purdue University Press
101 Trees in Indiana, Amazon
ID That Tree, Purdue Extension – Forestry and Natural Resources YouTube Playlist

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

 

 

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Curious about the upcoming cicada emergence? What is different about this species than the ones you see every summer? What effect can they have on wildlife or on your trees and shrubs? Find out from Purdue Extension wildlife specialist Jarred Brooke, forester Lenny Farlee and Purdue Entomology’s Elizabeth Barnes. Don’t miss the question and answer time with our experts discussing “all things cicadas”.

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:
17-year Cicadas Are Coming: Are You Ready?, Purdue Landscape Report
17 Ways to Make the Most of the 17-year Cicada Emergence, Purdue College of Agriculture
Periodical Cicada in Indiana, The Education Store, Purdue Extension resource center
Cicada Killers, The Education Store
Purdue Cicada Tracker, Purdue Extension-Master Gardener Program

Dr. Elizabeth Barnes, Exotic Forest Pest Educator
Purdue Department of Entomology

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

Jarred Brooke, Wildlife Extension Specialist
Purdue Forestry and Natural Resources

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In this edition of ID That Tree, Purdue extension forester Lenny Farlee explains how to identify shellbark hickory without the help from its leaves. He also shares about how to distinguish this native Indiana species from its close cousin, the shagbark hickory.

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
Hickory and Pecan Species, The Education Store, Purdue Extension resource center
Shellbark Hickory, Native Trees of Indiana River Walk, Purdue Fort Wayne
Shellbark Hickory, The Purdue Arboretum Explorer
ID That Tree Fall Color Edition: Shagbark Hickory, Video, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
ID That Tree, Playlist, Purdue Extension-FNR YouTube Channel
A Woodland Management Moment, Playlist, Purdue Extension-FNR YouTube Channel
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store

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

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

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

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

You might be asking yourself, ‘Why is a wildlife specialist writing about pollinators?’ It turns out that quality habitat for wildlife is often quality habitat for pollinators. The diversity of wildflowers and structure that native grasslands, trees and shrubs benefit them all. Trees such as eastern redbud and Ohio buckeye provide early nectar sources. Native grasslands that have a diverse mixture of wildflowers provide food, bare ground, and structure desirable for a wide variety of pollinators.

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

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

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