Purdue University - Extension - Forestry and Natural Resources
In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces the Paper Birch. This species is found in the North Woods of Northern Wisconsin and the Upper Peninsula of Michigan. This species has white chalky bark that peels and flakes off the sides of the tree. Under the bark, the tree tends to be a light tan to bronze color. They have alternate leaf arrangement, are catkins as part of their flowering structure, and have simple 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:
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
In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces the Black Ash. This species is typically found in wetland environments within Indiana and the North Woods of Northern Wisconsin. This species has light gray flaky bark, opposite leaf arrangement, and compound leaves. These trees separate very easily along their growth rings and thus have a long tradition of native peoples creating baskets with them. This species is under is a major threat by the emerald ash borer.
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)
Black Ash, Native Trees of Indiana River Walk, Fort Wayne-Purdue
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
In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces the Balsam Fir. This species is found in the North Woods of Northern Wisconsin and the Upper Peninsula of Michigan. It’s the primary fir found in the area and features soft and aromatic needles, which are flattened and have white stripes along the underside. Another notable characteristic is the three buds at the end of the twigs. This species can be easily identified from a distance due to its tight pointed spire like appearance.
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
Question: I have 2,700 young white oak and hickory trees that were planted in 2017 that now have black locust creeping in. Should I try to remove them by cutting them down and treating the stumps? What is the best treatment to control the brush?
Answer: Whether eliminating black locust competing with oaks in a tree planting, or controlling invasive woody shrubs like autumn-olive or Asian bush honeysuckles, cutting the stems near ground-line and treating the stumps with an appropriate herbicide provides a one-two punch to the target plant. Severing the stems from the roots cuts off the flow of photosynthesis-produced food to the roots, and may prevent production and ripening of seed, if done early enough in the growing season. The stump left behind provides a small target area for herbicide application, limiting the damage to nearby native plants that can result from foliar herbicide overspray and drift. The herbicide application should kill the roots and limit re-sprouting. While it requires two sequential operations, cutting and spraying, it may be one of the most efficient methods to control many smaller-diameter woody plants due to the high rate of control achieved when done correctly and limited damage to surrounding desirable vegetation.
So how do you do the “cut-stump” treatment correctly? Several factors need to be considered, but some common elements to effective and efficient treatments include a cutting tool you can operate safely, effective herbicide type and application, and correct timing for the site and situation. Tools can be powered by fuel or electric motors or by your muscles. Be sure you know how to operate them safely and wear appropriate safety gear. I prefer brush saws for near-ground cutting as it limits bending over and is safer to operate than a chainsaw, but they will struggle with some larger diameter or denser stems a chainsaw could cut easily. Handsaws, loppers, pruners, or blade-tools like machetes and brush-hooks are hand-tool options, but larger stems will require more time and effort to cut or will be too large for some hand-tools to handle. Herbicides should be applied immediately after you have cut off the stems. A good choice for many applications is herbicide containing the active ingredient Glyphosate. Glyphosate concentrate herbicides containing 42% or more active ingredient are widely available at many garden and farm stores. Read the label before using the herbicide to confirm the active ingredients, concentration, and requirements for safe and effective applications, including the appropriate safety gear during dispensing and application. Apply the concentrate straight or mixed with up to 50% water to the cut surface immediately after the cut is made. For stems over 3 to 4 inches in diameter, you can apply a band of spray around the perimeter of the stump so the bark, cambium and some sapwood is treated. If you wait to apply the spray to cut surfaces a dozen minutes to hours after the cut is made, two things will happen that can impact the effectiveness of the spray. The surface of the stump will seal as it dries, preventing the entry of the water/herbicide mixture into the plant. You may also have difficulty tracking down the cut stumps if the area is weedy and brushy.
Some cautions about timing and locations of this application method. Many plants are pumping lots of sap up from the roots in spring. That sap can flush herbicides out of the application area and result in herbicide failure and re-sprouting from the root system. If the stem is frozen, usually 25 degrees F or colder, herbicide may also not penetrate and evaporate off the frozen stump. Also avoid applications when rain could wash off the herbicide within two or three hours of application.
Several other herbicides are available for this treatment including Triclopyr and 2-4-D/Picloram herbicides. Be sure to read the labels and understand the safety requirements and application instructions before using.
For additional information see the Purdue Extension-FNR webinar Invasive Plants Threaten our Forests Part 2: Control and Management.
More resources:
District Forester, Indiana DNR Division of Forestry, for over 10 acres of woodlands
Directory of Professional Foresters, Indiana Forestry & Woodland Owners Association (IFWOA)
Indiana Woodland Steward E-newsletters, Eleven Member Organization
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
Forest Improvement Handbook, The Education Store
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
The Education Store, Purdue Extension’s resource center (place keywords in search bar, for ex: invasive, forest, timber)
Lenny Farlee, Extension Forester
Purdue University Department of Forestry and Natural Resources
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.

Photo of egg sacs of the hemlock woolly adelgid. These white “wool” balls are the most tell-tale sign of this pest.
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 – Got Nature? Blog, Purdue Extension – FNR
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
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
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
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
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.

Figure 3. Once dominated by large non-native bush honeysuckle shrubs, this site was recently cleared by large brush cutting equipment. (click to enlarge)
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
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 – Got Nature? Blog, Purdue Extension – FNR
Why Is My Tree Dying? – Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Tom Creswell, Plant & Pest Diagnostic Laboratory Director
Purdue Botany and Plant Pathology