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Purdue Landscape Report: The hemlock woolly adelgid (Adelges tsugae) continues its eastward spread across the US. In 2022, seven new counties were added to the distribution map of this invasive insect. While it is not present in Indiana yet, it is confirmed throughout the eastern USA from northern Georgia to Maine, extending west into Michigan, Ohio, and Kentucky.

Since its introduction in the 1950s, hemlock woolly adelgid has caused severe mortality of eastern hemlock in the United States. Not only is this a significant impact on our native tree diversity, hemlock losses are linked to a decline in several native bird species in the New England and mid-Atlantic forests (Ellison et al. 2018). In Indiana, eastern hemlock has a scattered native range in isolated locations of the west-central and southern regions of the state. It typically grows on steep slopes, canyons, and ravines. Hemlock woolly adelgid is also a threat to ornamental hemlocks, which are frequently used in landscaping.

Identifying Eastern Hemlock
Hemlock woolly adelgid will only feed on hemlocks, so proper tree identification is crucial. If you’re not sure whether your conifer is hemlock, check the color, shape, and arrangement of the needles. The needles of eastern hemlock grow singly (not in clusters) in alternate or opposite positions. The needles are flattened, and have two white stripes on the underside. The cones are small (1-2 cm), and when dry, they can resemble a rosette.

Monitoring for Hemlock Woolly Adelgid
The white “wool” balls are the most tell-tale sign of this pest. Check the undersides of the branches at the base of the needles, and look for small, round, white cottony masses that cover the twig. These are actually the egg sacs of the hemlock woolly adelgid. You may also notice the “crawlers”, or the mobile nymphs, which are tiny, oval-shaped, reddish-brown insects.

If you frequently check hemlock trees, you may see other white spots that resemble the woolly adelgid. The cocoons of elongate hemlock scale are often confused with hemlock woolly adelgid. However, note how the white “spots” from the scale infestation are flattened and cover the needles. Hemlock wooly adelgids congregate at the base of the needles along the twig, not on the needles themselves, and the egg sacs are round in shape. Single, large egg sacs found throughout the branch are often spider egg sacs or oak skeletonizer cocoons.

Report any suspected findings of hemlock woolly adelgid at the Early Detection Distribution Map System (EDDMapS) website.

To view this original article and other Purdue Landscape Report articles, please visit Purdue Landscape Report.

Resources:
ID That Tree: Eastern Hemlock, video, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
Distinguishing Hemlock From Yew, The Purdue Landscape Report
Normal Needle Drop: Even Healthy Evergreens are not Evergreen, Purdue Plant & Pest Diagnostic Lab (PPDL)
Recognizing and Managing Poison Hemlock, Purdue Landscape Report
Be Careful Around Highly Toxic Poison Hemlock Plant This Summer, Purdue Extension – FNR
Phomopsis Dieback of Spruce, The Education Store, Purdue Extension resource center
Chlorosis of Pine Trees, The Purdue Landscape Report
Borers of Pines and Other Needle Bearing Evergreens in Landscapes, The Education Store
Stress-related Conifer Dieback, The Education Store
Certified Soil Testing Laboratories, Purdue Extension-Master Gardener Program
Tree Installation: Process and Practices, The Education Store
Planting Your Tree Part 1: Choosing Your Tree, video, Purdue Extension – FNR YouTube Channel
Tree Defect Identification, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Tree Risk Management, The Education Store
Consumer Horticulture: Collecting Soil Samples for Testing, The Education Store
Find an Arborist website, Trees are Good, International Society of Arboriculture (ISA)
Purdue Pest and Plant Diagnostic Lab, send in photo or samples

Alicia Kelley, Cooperative Agricultural Pest Survey (CAPS) Coordinator
Purdue Extension – Entomology

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This native Indiana shrub can be found on the edge of standing water and in wetlands. In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to the buttonbush, which is known for its attractive round flowers in mid-summer, which are a favorite of pollinators, and its simple leaves, which are held in a whorled arrangement.

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, Playlist, Purdue Extension – Forestry and Natural Resources YouTube Channel (Invasive White Mulberry, Siberian Elm, Tree of Heaven)
Invasive Species Playlist, Playlist, Purdue Extension – FNR YouTube Channel (Asian Bush Honeysuckle, Burning Bush, Callery Pear, Multiflora rose)
A Woodland Management Moment, Playlist, Purdue Extension – FNR YouTube Channel (Against Invasives, Garlic Mustard, Autumn Olive)
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR YouTube Channel (Common Buckthorn, Japanese Barberry)
Report Invasive Species, Purdue Invasive Species
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMaps – Early Detection and Distribution Mapping System
How long do seeds of the invasive tree, Ailanthus altissima remain viable? (Invasive Tree of Heaven), USDA Forest Service
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council
Cooperative Invasive Species Management Area (CISMA)
Aquatic Invasive Species, Illinois-Indiana Sea Grant (IISG)
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
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store, Purdue Extension Resource Center
Native Trees of the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
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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Purdue Landscape Report: Some of the questions that I get asked quite frequently are “Are my trees ok?”, “Do I need to have an arborist come work on my trees?”, and “Is there anything I can do to help my trees without hurting my savings?”. Just like many questions, the answers are dependent on the situation. There are a multitude of cases where it is in the best interest of both you and the tree to hire a professional. From removals and storm damage, to pruning at height and/or around utilities, and other dangerous situations, you really should invest in the cost of a certified arborist. But there are instances where you can save some money and feel the pride of caring for your trees yourself by doing some of your own pruning work.

You might not think too much about pruning. Maybe you feel like “Hey! Anyone can cut off a branch”, and you’re right but also not. There is a right and wrong way to pruning and cleaning out dead wood. Depending on where you cut and how much you remove, you might end up doing more damage to your tree and end up requiring the assistance of an arborist earlier than needed. For the pruning layperson, there are several topics that can help you prune like a pro: safety, equipment, and proper pruning cuts.

First and foremost is safety. From this time of the year onward it’s only going to get hotter, but it’s important to protect your body from accidents with your tools, from the elements, and even from the plants you’re pruning by wearing the proper personal protective equipment (PPE). From the toes up, skilled professionals have their work boots (closed toed shoes), pants (not shorts), at the very least a t-shirt, gloves and safety glasses, and hearing and head protection depending on the equipment and scale of work. And if you’re using power equipment like chainsaws make sure you’ve got protective chaps for that added level of safety.

The standard equipment available for pruning includes hand pruners, loppers, and hand and pole saws (I’ll touch on chainsaws more in a later article). The two main types of pruners and loppers are called bypass and anvil styles. Bypass pruners have two blades that “bypass” each other like scissors, leaving clean cuts on your trees and shrubs. Anvil pruners have a single blade that shuts against a flat surface, the “anvil”, and can leave bruised or crushed plant material after cuts. Use your hand pruners for smaller cuts (up to 3/4” in diameter depending on the quality of your blade) and your loppers for larger diameters that might not require a hand saw.

When choosing a hand or pole saw, it is best to have one specifically designed for pruning. Pruning saws come in different configurations. They can be straight or curved, have fixed or folding blades, and come in different lengths and teeth sizes. A good rule of thumb is shorter blades or blades with smaller teeth for finer pruning cuts and longer blades with larger teeth for bigger diameter limbs (pole saws will usually have larger blades attached to single or extendable poles). You’ll also want a blade that isn’t so thin that it buckles on the first cut. For pruning at home, I recommend a 10-12” saw with medium sized teeth. That coupled with a hand pruner and some loppers should cover most of your pruning projects.

Now that you have your PPE and your pruning equipment you’ll want to begin cutting, but there are some considerations along with dos and don’ts for pruning. First, you want to decide what your goals are (raising the canopy off the ground or a building, thinning the crown to increase light and/or wind, or reducing the canopy by shortening limbs) and how much you need to remove from your tree (Fig. 1). In most cases, less is more. Whenever you remove plant material you are doing two things:

1) you are injuring the tree, exposing open cuts to pests, diseases, and the elements

2) you are removing plant material that could continue to create energy for the tree if left on.

Both will stress your tree and it will need time to adapt and heal. You can always remove more later, but once you make your cuts you cannot put them back. If your tree needs a heavier prune, it’s time to bring in an arborist.

Next you need to consider what are you cutting? Are you removing whole limbs back to the trunk or are you shortening limbs? If you are removing limbs you want to avoid flush cuts, cutting back even to the trunk. Flush cuts (Fig. 2) are usually oval and have a larger surface area exposing more of the tree to pests, diseases, and the elements. Instead, you want to cut up to the branch bark ridge, a raised portion of bark on the top of the limb where it meets the trunk, and the branch collar, usually a swollen area on the bottom side of the limb where it begins to flare out from the trunk (Fig. 3). This is a proper removal cut that has the smallest surface area exposed and is usually more circular than oval.

If you are shortening limbs you want to perform a reduction cut, which is removing a larger stem by cutting back to a lateral branch that is at least 1/3 the diameter of the portion you are removing (Fig. 4). This provides sufficient energy production the keep the remaining limb alive. In this situation, you want to avoid heading cuts, which are length reductions without regard to the position or diameter of the lateral branch you are cutting back too. Cutting too far away from the lateral will lead to dead stubs that increase exposure and the time needed to heal over wounds. Cutting to laterals that are too small won’t allow the limb to produce enough energy to survive.

Last, whether you are applying removal or reduction cuts, you want to utilize what is called the ternary or 3-Cut Method (Fig. 5). The purpose of this method to stop damage from splitting and tear-outs in larger limbs that can’t be controlled by hand. The first cut is the undercut, about 1/3 the diameter of the limb and usually 6-12 inches from your final cut. The second cut is the top cut just outside the undercut. This cut continues down until it meets the same plane as the undercut where gravity will take hold as the branch snaps and falls. The final cut is to the branch collar, or the chosen lateral as noted above.

Proper pruning can be a daunting task at first. With time, the correct materials, and practice you can better care for your trees, your landscape, and yourself. If you are still worried about your trees, there are plenty of resources at Purdue Extension and The Education Store or you can always find an ISA Certified Arborist nearby using the Trees Are Good website. They will be able to help assess any other issues and provide excellent professional help.

Resources:
Tree Pruning Essentials, Video & Document
Tree Pruning for the Landscape Webinar, Purdue Extension – Forestry and Natural Resources (FNR) Youtube Channel
Tree Appraisal and the Value of Trees, The Education Store, Purdue Extension resource center
Tree Pruning: What Do Trees Think?, 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: Choosing a Tree, The Education Store
Tree Planting Part 2: Planting Your Tree, The Education Store
Planting Problems: Planting Too Deep, Video, Purdue Extension – FNR Youtube Channel

Ben McCallister, Urban Forestry Specialist
Purdue Forestry and Natural Resources

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In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces the yellow buckeye. This native species, found in southeastern Indiana on high quality sites, features palmately compound leaves, like fingers on a hand, mostly featuring five leaflets with lighter colored undersides. This species is named for its yellow flower clusters, which appear in the spring. It holds its buckeye seeds in smooth husks, unlike its cousin Ohio buckeye, which has warts and spines.

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, Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel (Invasive White Mulberry, Siberian Elm, Tree of Heaven)
Invasive Species Playlist, Playlist, Purdue Extension – FNR YouTube Channel (Asian Bush Honeysuckle, Burning Bush, Callery Pear, Multiflora rose)
A Woodland Management Moment, Playlist, Purdue Extension – FNR YouTube Channel (Against Invasives, Garlic Mustard, Autumn Olive)
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR YouTube Channel (Common Buckthorn, Japanese Barberry)
Yellow Buckeye, Native Trees of Indiana River Walk, Purdue University, Fort Wayne
Report Invasive Species, Purdue Invasive Species
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMaps – Early Detection and Distribution Mapping System
How long do seeds of the invasive tree, Ailanthus altissima remain viable? (Invasive Tree of Heaven), USDA Forest Service
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council
Cooperative Invasive Species Management Area (CISMA)
Aquatic Invasive Species, Illinois-Indiana Sea Grant (IISG)
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
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store, Purdue Extension Resource Center
Native Trees of the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
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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Purdue Agriculture News – Purdue Extension has been selected to support a multistate effort to help rural, tribal and underserved communities access federal funding for energy and environmental improvement efforts.

The University of Minnesota will lead the effort as an Environmental Justice Thriving Communities Technical Assistance Center (TCTAC) for Region 5 with funding from the U.S. Environmental Protection Agency. Purdue Extension’s Community Development program will provide central support in Indiana to help communities navigate federal grant application systems, identify partners and matching funds, and assist with project design and development.

“Purdue Extension is positioned well to connect with rural and underserved communities across Indiana with staff in all 92 counties,” said Kara Salazar, assistant program leader for Purdue Extension Community Development and sustainable communities extension specialist. “We look forward to working with regional partners as a liaison for communities in need of resources to assist with clean energy and water, affordable and sustainable housing, and addressing legacy pollution.”

Additional partners in Indiana include the North Central Regional Center for Rural Development (NCRCRD), Illinois-Indiana Sea Grant and Purdue Center for Regional Development (PCRD).

Michael Wilcox, associate director of NCRCRD and assistant director and program leader of Purdue Extension Community Development, welcomes interested community partners to reach out to get involved.

“We look forward to connecting with communities across the state while collaborating with our partners across the EPA Region 5. This is another excellent example of states within the north central region working together as partners to address pressing issues while fostering community resilience,” he added.

“Illinois-Indiana Sea Grant is enthusiastic to build on our ongoing programs as we partner on this broad project to help support underserved coastal communities around southern Lake Michigan and throughout the Great Lakes in addressing environmental challenges,” said Tomas Höök, director of Illinois-Indiana Sea Grant and professor in Purdue University’s Department of Forestry and Natural Resources.

Resources:
Implementation Examples of Smart Growth Strategies in Indiana, The Education Store, Purdue Extension’s resource center
Conservation Through Community Leadership, The Education Store
Community Development, Purdue Extension
Conservation Through Community Leadership, video, Purdue Extension You Tube Channel
Rainscaping Education Program, Purdue Extension
Rainscaping and Rain Gardens, Purdue Extension YouTube Channel
Enhancing the Value of Public Spaces, The Education Store
Enhancing the Value of Public Spaces: Creating Healthy Communities, The Education Store
Enhancing the Value of Public Spaces Program, video, Purdue Extension YouTube Channel
Community Planning Playlist, Purdue Extension-Forestry & Natural Resources (FNR) YouTube Channel
Indiana Creek Watershed Project – Keys to Success, Partnerships and People, Subscribe to Purdue Extension-FNR YouTube Channel

Abby Leeds, Senior Communications Specialist
Purdue Agricultural Communications

Michael Wilcox, Associate Director & Program Leader
North Central Regional Center for Rural Development (NCRCRD) & Purdue Extension Community Development

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Illinois-Indiana Sea Grant Newsroom – During large rainstorms, many Illinois residents brace themselves for flooding in their basements, streets and neighborhoods. A new online tool, Illinois Groundwork, provides communities and stormwater professionals with resources on green stormwater infrastructure, which provides a way for rain to be absorbed into soil where it lands.

Green stormwater infrastructure offers a way to enhance traditional or “grey” infrastructure using a rain garden or permeable pavement but this approach doesn’t always work as well as it might. Improving access to, and use of, data, research and other resources can help increase the effectiveness of green infrastructure in addressing stormwater management challenges.

“The University of Illinois not only has relevant research and data across many departments, but also real-world examples of successful green infrastructure, along with other extension and education tools, such as the Red Oak Rain Garden,” said C. Eliana Brown, University of Illinois Extension stormwater specialist. “This new tool brings these resources together, providing a robust platform to access green infrastructure knowledge.”

The project is a collaboration of Illinois–Indiana Sea Grant and Illinois Extension. A critical component of Illinois Groundwork is an Illinois-Indiana Sea Grant (IISG)-funded research project that focused on incorporating soils data into green infrastructure design. Soils are the foundation of effective green stormwater infrastructure performance.

“Soil characteristics establish how much and how fast water can move through and absorb into the soil,” explained Margaret Schneemann, IISG water resource economist. “Failing to take soils performance into account means we are not designing green infrastructure as cost-effectively as we could be and may be leaving its benefits on the table.”

For full article . . .

Illinois-Indiana Sea Grant is a partnership between NOAA, University of Illinois Extension, and Purdue University Forestry and Natural Resources, bringing science together with communities for solutions that work. Sea Grant is a network of 34 science, education and outreach programs located in every coastal and Great Lakes state, Lake Champlain, Puerto Rico and Guam.

More Resources:
Implementation Examples of Smart Growth Strategies in Indiana, The Education Store, Purdue Extension’s resource center
Conservation Through Community Leadership, The Education Store
Conservation through Community Leadership, Purdue Extension You Tube Channel
Rainscaping Education Program, Purdue Extension
Rainscaping and Rain Gardens, Purdue Extension YouTube Channel
Enhancing the Value of Public Spaces, The Education Store
Enhancing the Value of Public Spaces: Creating Healthy Communities, The Education Store
Enhancing the Value of Public Spaces Program, Purdue Extension YouTube Channel
One Water Approach to Water Resources Management, The Education Store
Community Development, Purdue Extension
Community Planning Playlist, Purdue Extension-Forestry & Natural Resources (FNR) YouTube Channel
Indiana Creek Watershed Project – Keys to Success, Partnerships and People, Subscribe to Purdue Extension-FNR YouTube Channel
Climate Change and Sustainable Development, The Education Store
Climate Change: Are you preparing for it?, The Education Store

Illinois-Indiana Sea Grant

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Everyone experiences phenology. What is phenology and how can observing plant and animal life cycle stages help us understand changes in climate, water, light and other abiotic factors? In this webinar hosted by Indiana Forestry & Woodland Owners Association (IFWOA), presenter Amanda Wanless of Indiana Phenology explains what phenology is and how each season is unique. Phenology includes the leafing and flowering, the ripening of crops in the fields,  the emergence of insects, the migration of birds and much more.  Amanda discusses how you can observe seasonal change on the landscape, and ways to monitor on your own or join a citizens science network collecting long term data.

Check out the Indiana Forestry & Woodland Association YouTube Channel for videos including: What is IFWOA?; A New Carbon Program for Hardwood Landowners Webinar, Indiana’s Native Orchids, Magnificent Trees of Indiana, Be Tick Aware and much more.

The Indiana Forestry & Woodland Owners Association (IFWOA) was founded in 1977 and is a non-profit organization dedicated to conservation and sustainable management of woodlands in Indiana. IFWOA advocates for scientific best practices for management to achieve objectives of clean water, wildlife habitat, soil protection, native species diversity, timber production, recreation, carbon sequestration and many others.

IFWOA is an affiliate of the National Woodland Owners Association. IFWOA is a partner, collaborator or is represented on leading National and State organizations. These memberships or collaborations are selected to advance Indiana Woodland owner’s interests. IFWOA monitors and influences legislation and economic trends impacting Indiana woodlands and landowners for our members. Membership in IFWOA provides a valuable network linkage to information and resources at the leading edge of science, industry and politics impacting Indiana woodlands.

Resources:
Magnificent Trees of Indiana, Purdue University Press
Forest Improvement Handbook, The Education Store, Purdue Extension’s resource center
Planting Hardwood Seedlings – The Education Store
Ordering Seedlings from the State Forest Nursery System, Got Nature? – Purdue Extension-FNR
Importance of Hardwood Tree Planting – The Education Store, Purdue Extension Resource Center
Forest Improvement Handbook – The Education Store
Designing Hardwood Tree Plantings for Wildlife – The Education Store
ID That Tree – YouTube Playlist
Forest Management for Reptiles and Amphibians: A Technical Guide for the Midwest, The Education Store
Hardwood Ecosystem Experiment – Forest Birds , Purdue Extension – FNR YouTube Channel
Managing Woodlands for Birds , Purdue Extension – FNR YouTube Channel
Sustaining Our Oak-Hickory Forests , Purdue Extension – FNR YouTube Channel
Ask the Expert: Hardwood Ecosystem Experiment – Birds and Salamander Research, Purdue Extension – FNR
Subscribe to Purdue Extension-FNR YouTube Channel

Liz Jackson, Engagement Lead
Indiana Forestry & Woodland Association

 

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Question: Once I’ve pulled or cut, and have treated the bush honeysuckle stumps, can it be left to decay, particularly if not piled directly on the ground in a woodland?

When deciding what methods to use to control invasive brush on your property, one of the questions often asked is “what should I do with the cut tops?” (Fig. 1) A similar question we often get from landowners planning to have timber harvested from their woods is “what should I or the loggers do with the tree tops that are left?” The simple answer is just leave them where they are and they will decay over time and gradually disappear. If you have many acres to treat for invasive brush infestation, then this is good news. But there may be other factors to consider. In this blog post I will try to unpack those other considerations to help you decide what to do.To start let’s do a quick review of the more common methods of controlling invasive brush and the resulting ground conditions left in their aftermath. By invasive brush, I am primarily talking about non-native brush species that have invaded our native habitats, including the woods, and that are wreaking ecological havoc and degrading the productive potential of those lands for wildlife, timber, and recreation. The more common species include Asian bush honeysuckle, autumn olive, multiflora rose and callery pear (aka Bradford, Cleveland, ornamental pear).There are a variety of methods, tools, equipment, and chemicals used for invasive brush control. Other blog posts cover many of these methods, so I will not describe their use except to show what a site looks like in their wake. Large equipment like skid steer mounted mulchers or brush cutters or the industrial size Hydroax (Fig. 2) thoroughly chop up or mulch all that brush material and leave a fairly clean site (Fig. 3). In this case, there are no brush tops to dispose of. If you are wanting a very “clean” site, then hiring a dozer may be what you’re after. All those tops can then be piled and burned. The bare soil can then be planted in desired vegetation.Most forest landowners are going to use smaller scale methods and equipment, especially in the woods. Spraying herbicide on the foliage (Fig. 4) or applying it as a basal bark application to the lower stems leaves dead standing shrubs. Using brushsaws and chainsaws to cut the shrubs close to the ground and then applying a concentrated herbicide to the stump (commonly called cut-stump treatment, Fig. 5) leaves severed brush tops lying about. Even the less conventional prescribed fire will almost always leave standing dead shrub tops.

For many people, the problem with all these dead shrubs lying about is aesthetic – it makes the property look cluttered, at best, if not downright unsightly. If aesthetics were the only concern, we might be able to talk ourselves into putting up with it for several years until the dead shrub tops begin to decay and break down and new vegetation grows up to mask them.

But are there other concerns that would justify expending time and money to dispose of the dead tops?
Access may be another consideration, especially in high use areas such as those used frequently for recreation like hunting or hiking. Depending on habitat restoration plans, you may want access to those areas to seed or plant native trees, shrubs, forbs or grasses. Especially if you are using specialized planting or seed drill equipment, the site may need to be relatively clear of obstructions and debris.

How does leaving dead invasive shrub tops impact this restoration process?
The removal of invasive species should not be the end goal in managing habitat, but only an important step in restoring a healthy native plant community. How does leaving dead invasive shrub tops impact this restoration process? Researchers in Ohio found in the short term that cutting and applying herbicide to the stumps of Amur honeysuckle (Asian bush honeysuckle) and leaving the tops in place allowed more sunlight to reach the forest floor than the basal bark treatment which left dead tops standing in place (Cipollini et al. 2009). This resulted in greater height growth for native herbaceous plant growth. However, in the presence of deer browse, the native plants suffered less deer damage in the basal bark treatment area, due to the greater protection afforded by the standing dead tops, compared to the areas where tops were cut. One might surmise that even leaving cut tops in place may provide some protection from deer browse compared to complete removal of the tops. Joshua Shields and fellow researchers at Purdue University (2014) studied the impact of clearing bush honeysuckle in a forest environment on white footed mice populations. They found that where bush honeysuckle was cut and the tops removed from the site that white footed mice numbers increased, compared with mice numbers in nearby standing live bush honeysuckle. They did not, however, test how leaving cut honeysuckle tops on site would affect mice populations.

Many people may cringe at the thought of increasing numbers of mice, but mice in their natural environment are an important source of food for many predators, including hawks, owls, fox, mink, weasels, and bobcats. In a study comparing the cut stump method (cutting the stems and treating the stump with herbicide) and the use of a mulching head attachment on a skid steer for controlling bush honeysuckle, Purdue researchers found no difference in the growth and recovery of the native plants (Graham et al. 2018). However, the mulching head treatment resulted in a greater abundance of garlic mustard, a non-native invasive biennial herb. Invasive brush control treatments resulting in greater soil disturbance often lead to a second wave of invasive plants that need follow-up treatment.

So what can we conclude from all this?
There are benefits and drawbacks to removing invasive brush tops when managing invasive species on your property. It really depends on your management objectives. It can even vary depending on the specific location on your property. In some select areas it may be very beneficial to remove the tops while in most other areas you can just let them rot in place. The important thing is that you have a well thought out plan for managing the invasive species on your property and that you are working your plan. As you work your plan you will begin seeing the positive results as native plant communities begin to make a comeback.

Resources:
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources (FNR) Youtube Channel
Conservation Tree Planting: Steps to Success, Purdue Extension – FNR Youtube Channel
Invasive Species, Playlist, Purdue Extension – FNR Youtube Channel
Woodland Stewardship for Landowners, Playlist, Purdue Extension – FNR Youtube Channel
Invasive Plant Species Identification, Video, Purdue Extension – FNR Youtube Channel
Report Invasive Species, Purdue Invasive Species
The GLEDN Phone App – Great Lakes Early Detection Network
EDDMaps – Early Detection and Distribution Mapping System
Indiana Department of Natural Resources: Invasive Species
Indiana Invasive Species Council
Cooperative Invasive Species Management Area (CISMA)
Invasive plants: impact on environment and people, The Education Store, Purdue Extension’s resource center
A Landowner’s Guide to Sustainable Forestry: Part 7: Managing for a Diversity of Value-Added Forest Products, The Education Store
Investing in Indiana Woodlands, The Education Store
Woodland Invaders, Got Nature? Blog, Purdue Extension – FNR

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

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Purdue Landscape Report: Each spring the PPDL receives several samples of oak trees showing curled, twisted, stunted and/or generally ratty looking leaves. When there are holes in the leaves or leaf edges are missing tissue, we add another symptom name to the mix: tatters.

Distorted new growth and tatters are most common on white oaks and may occasionally show up on red oak, hackberry and other trees. Upon initial inspection the leaves look as if they have been shredded or severely fed upon by insects. However, a closer observation of the leaves will reveal that the leaf tissue has not been removed, but rather, it never developed normally.  We have seen this problem on white oaks for many years in Indiana and it has been reported in other states throughout the Midwest.

Several possible causes for this symptom have been proposed, including poor growing conditions, insect injury, leaf diseases, late spring frost damage and herbicide drift; however, no single factor serves to explain all the cases. In 2020 we saw a distinct link between tattered oak leaves and a late spring frost that year but the connection is not always so clear cut. See PLR article: Oaks Will Persist After Ugly Summer Start.

Researchers have shown that acetochlor and s-metolachlor drift can cause tatters-like symptoms but results were variable, and in some treatments red oaks were more affected than white oaks, contrary to the expected results. In many instances there is no direct link to herbicide drift. We once had samples from a white oak tree that showed symptoms of tatters and leaf curl every year, yet was located in the middle of a heavily forested area miles away from any agricultural fields that might have been a source of herbicide drift. While the exact cause may not be clear, it does appear that conditions that lead to tatters occur while the leaves are still developing.

To view this full article and other Purdue Landscape Report articles, please visit Purdue Landscape Report.

Subscribe and receive the newsletter: Purdue Landscape Report Newsletter.

Resources:
The Purdue Landscape Report
Certified Soil Testing Laboratories, Purdue Extension-Master Gardener Program
Consumer Horticulture: Collecting Soil Samples for Testing, The Education Store
Purdue Landscape Report Facebook Page
Find an Arborist website, Trees are Good, International Society of Arboriculture (ISA)
Tree Installation: Process and Practices, The Education Store
Planting Forest Trees and Shrubs in Indiana, The Education Store
Planting Your Tree Part 1: Choosing Your Tree, Video, Purdue Extension – Forestry and Natural Resources YouTube Channel
Tree Defect Identification, The Education Store, Purdue Extension resource center
Tree wounds and healing, Got Nature? Blog
Tree Pruning Essentials, Publication & Video, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Tree Risk Management, The Education Store
Why Is My Tree Dying?, The Education Store

Tom Creswell, Plant & Pest Diagnostic Laboratory Director
Purdue Botany and Plant Pathology

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In this episode of A Woodland Management Moment, Purdue Extension forester Lenny Farlee talks about the high deer populations around forest land, which can make it difficult to get hardwood seedlings established. This video brings more details and introduces a revised less expensive design option as it coincides with our first deer fencing video.

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

Resources:
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store, Purdue Extension Resource Center
Native Trees of the Midwest, The Education Store
ID That Tree, Playlist, Purdue Extension – FNR YouTube Channel
Investing in Indiana Woodlands, The Education Store
Woodland Stewardship for Landowners Video Series, Playlist, Indiana Department of Natural Resources YouTube Channel
Ask an Expert: Tree Selection and Planting, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel

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

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