Got Nature? Blog

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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As trees grow and reach heights which many consider to be unsafe, tree owners would often top their trees by reducing the tree size. This is by heading back most of the large, live branches from the tree. However, topping trees proves to be more damaging than beneficial.

Topping trees can cause decay, weak branch attachments, and an increased likelihood of failure. If we do not top our trees and leave them to develop naturally, the structural strength of the trees is stronger than those that are not topped. The extensive root system, when left undisturbed, provides adequate support for the trees.

This publication titled What’s Wrong with Topping goes in-depth on the implications of topping and provides better alternatives to topping.

To view other urban forestry publications and video resources, check out Purdue Extension’s The Education Store website.

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

Lindsey Purcell, Urban Forestry Specialist
Purdue 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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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:
Billions of Cicadas Are Coming This Spring; What Does That Mean for Wildlife?, Got Nature? Blog, Purdue Extension-Forestry and Natural Resources (FNR)
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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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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Purdue Landscape Report: The hard freeze April 20th & 21st had many homeowners concerned about their perennial and annual plants in their landscape.  For the vast majority of perennial plants, there aren’t many issues long-term of concern.  Some foliage and flowers have significant damage, but the plants will recover, and possibly release new vegetative buds in severe cases.  The plants that suffered the most damage, and in some cases death, are the annuals planted by impatient landscapers and gardeners.  Planting annuals prior to the frost-free date (May 10^th in central Indiana) will more than likely cause a replant to occur.

In addition to the potential stress from the temperatures, many trees received broken limbs due the combined weight of the leaves/flowers and snow load.

If you maintain a client’s fruit trees (i.e. apples), there may be a significant impact on fruit production.  The Purdue Meigs Horticultural Research Farm, located about eight miles south of the West Lafayette campus, recorded a low temperature of 22^o F on April 21^st.  Dr. Peter Hirst, pomologist, indicated that at the current stage of flowering a temperature of 25^o F might result in a 90% bud kill.  Since there was a significant snowfall, the hope is that there was some moderation in temperatures.

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Question: I am actually a Master Gardner in Hamilton County and I need help with a tree bark damage question. We have a beautiful dogwood tree that is about 18’ tall and 6” in diameter. By accident my husband backed into the tree with his truck while unloading mulch – he did not see it! Now there is severe damage to the bark at the bumper height – about 3” wide and 14” long. All the way down the bark is gone.

What are the chances the tree will survive? What if anything should I do at this point?

My husband wanted to cover it with painter’s tape to protect it but I know that is not good for the tree. Please let me know your suggestions as I do hope to save the tree if possible.

Answer: Well, that is certainly an unfortunate accident for the tree! There may be a rescue treatment worth trying that research has shown promise in sealing the wound. The ability for the tree to seal and close off wounds is based on species, age and energy resources. Additionally, follow these instructions…

1. Keep the tree healthy; mulch and supplemental watering during drought conditions.
2. Trace the wound with a wood file and sharp knife, removing any loose bark to a clean wound.
3. Take black plastic and attach it to the tree wound, just past the wound edge, using small, ¼” staples from a staple gun.
4. Attach the plastic so that it forms a seal which will help to maintain a moist environment for parenchyma cells to do their work at compartmentalizing and creating wound wood on the perimeter of the damaged area.
5. The plastic may need to be checked periodically to be sure it is attached well until removal.
6. Leave the wound covered for about 12 months, then remove carefully.

This will not guarantee recovery, but research has indicated it does facilitate healing more quickly in many species. Continue to monitor for health and recovery.

Good luck!

Resources
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Equipment Damage to Trees, Got Nature? Blog
Tree Defect Identification, The Education Store, Purdue Extension resource center
Tree Pruning Essentials, Publication & Video, The Education Store
Tree Pruning: What Do Trees Think?, The Education Store
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Planting Part 1: Choosing a Tree, Video, Purdue Extension Channel
Tree Planting Part 2: Planting Your Tree, Purdue Extension Video

Lindsey Purcell, Chapter Executive Director
Indiana Arborist Association

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On this winter edition of ID That Tree, Purdue Extension forester Lenny Farlee uses black walnut and eastern cottonwood twigs to show you tips on how to identify native Indiana trees with alternative leaf arrangement without help from the leaves.

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
Black Walnut, The Education Store, Purdue Extension resource center
Facts About Black Walnut, The Education Store
Indiana Walnut Council, Industry Representatives include 45 states and 3 foreign countries
Cottonwood, The Education Store
Eastern Cottonwood, Native Trees of Indiana Riverwalk
FNR Hardwood – Eastern Cottonwood, The Purdue Arboretum Explorer
ID That Tree, Playlist
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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