Purdue University - Extension - Forestry and Natural Resources
The swallow-worts (also called dog strangling vine) are perennial, herbaceous, twining vines. The two species of principal concern in North America are black and pale swallow-wort. Black swallowwort is native to southwest Europe; pale swallow-wort is native to Ukraine and parts of Russia. Both were introduced to North America in the 1800s as potential ornamental plants.
Although swallow-worts are not yet well established in Indiana, their vines are highly invasive and grow vigorously, quickly twining around, and will climb anything nearby such as trees and shrubs or even man-made structures. This can overwhelm nearby plants by physically shading them, weighing them down, causing stem breakage, and forcing them to compete for moisture and nutrients.
At the time of writing, nine counties in central and northern Indiana reported small populations of black swallow-wort ranging in size from 10 square feet to 2,500 square feet of the infested area. Along Indiana’s border, two Michigan counties and the Chicago area report significant populations of black swallow-wort. No records of pale swallow-wort have been reported for Indiana. Two Michigan counties bordering northern Indiana and a central Illinois county are the nearest reported populations of pale swallow-wort.
This publication, Invasive Plant Series: Swallow-worts, aids in identifying these swallow-worts and provides management recommendations focused on prevention of spread, early detection, and properly timed and targeted control measures.
Resources:
Invasive Species, Playlist, Purdue Extension YouTube Channel
Invasive Plants Threaten Our Forests Part 1: Invasive Plant Species Identification, Webinar, Purdue Extension – Forestry and Natural Resources YouTube Channel
Invasive Plants Threaten Our Forests Part 2: Control and Management, Webinar, Purdue Extension – FNR YouTube Channel
Indiana Invasive Species Council
Report Invasive, Purdue Extension
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 resource center
Invasive Plant Species Fact Sheets: Poison Hemlock, The Education Store
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Ronald Rathfon, Regional Extension Forester Southern Indiana Purdue Agriculture Center (SIPAC)
Purdue Department of Forestry and Natural Resources
In this episode of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to the flowering dogwood, which blooms in April and May, and is a great alternative to the invasive callery pear. Learn more about this small tree and its growing preferences inside.
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
A Woodland Management Moment, Playlist, Purdue Extension – FNR YouTube Channel
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Native Trees of the Midwest, Purdue University Press
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
Flowering Dogwood, The Purdue Arboretum Explorer
Flowering Dogwood, Native Trees of Indiana River Walk, Purdue – Fort Wayne
Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources
In this episode of A Woodland Management Moment, Purdue Extension forester Lenny Farlee shares about some of the spring ephemeral plants, as well as shrubs, trees and even invasive species you may find in the forest understory.
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
ID That Tree, Playlist, Purdue Extension – FNR YouTube Channel
Invasive Species, Playlist, Purdue Extension – FNR YouTube Channel
Garlic Mustard, Purdue Extension – FNR YouTube Channel
Invasive plants: impact on environment and people, The Education Store, Purdue Extension resource center
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Native Trees of the Midwest, Purdue University Press
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
Woodland Invaders, Got Nature? Blog
Resources and Assistance Available for Planting Hardwood Seedlings, The Education Store
Woodland Stewardship for Landowners Video Series, Playlist, Indiana Department of Natural Resources YouTube Channel
Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources
Purdue Landscape Report: While fungi are responsible for many of our foliar disease problems, different fungal pathogens present as problems throughout the country, depending upon the host plant grown and the environmental conditions. This is a brief overview of several common types of fungal leaf diseases that occur in Indiana and throughout North America (and Europe). Recognizing the symptoms and signs is an important first step to diagnose a disease problem, followed by how to manage these diseases by combining cultural and chemical controls.
Common fungal leaf diseases of deciduous trees and shrubs
Anthracnose. Anthracnose diseases probably are the best-known foliar fungal diseases of deciduous trees. They affect many ornamental trees including major shade-tree genera such as sycamore (Platanus spp.), oak (Quercus spp.), maple (Acer spp.), elm (Ulmus spp.) and ash (Fraxinus spp.) (Fig. 1). Anthracnose actually is a general term describing symptoms such as dead irregular areas that form along and between the main vein of the leaf. The leaves may also become curled and distorted and twigs may die back. The fungus overwinters in infected twigs and the petioles of fallen leaves, and the spores disseminate in the spring by wind and splashing rain. The disease, while unsightly, rarely results in the tree’s death. Sycamores and other trees often withstand many years of partial defoliation. However, one anthracnose disease is more serious. Dogwood anthracnose (Discula destructiva) is a devastating problem on the Eastern seaboard, but has not been a significant issue here in Indiana.
Leaf blisters result in the blistering, curling and puckering of leaf tissue. Oak leaf blister (Taphrina caerulescens) is a common blister disease of oaks (Fig. 2)., particularly the red oak subgenus, which includes Northern red oak (Q. rubra) and pin oak (Q. palustris) among others. The symptoms begin as a slight yellowing of the infected leaf followed by round, raised blisters. These turn brown, and the infected leaves fall prematurely. This fungus overwinters as spores on the buds.
Leaf spot is a general symptom caused by a multitude of pathogens and infect all deciduous trees and shrubs, and include dead spots with a defined boundary between living and dead tissue. The dead tissue often separates from the surrounding living tissue creating a “shot-hole” appearance on the infected leaves. Common hosts include dogwood, maples, hydrangea, rose, holly, and Indian-hawthorn.
Tar spot (Rhytisma spp.) is a leaf disease with initial symptoms similar to leaf spot. The disease is most common on red (Acer rubrum) and silver maple (A. saccharinum) (Fig.3), but it can occur on a wide range of maple species from sugar (A. saccharum) and Norway (A. platanoides) to bigleaf maple (A. macrophyllum). The symptoms begin in the spring as small greenish-yellow spots on the upper leaf surface that, by mid-summer, progress to black tar-like spots about 0.5 inch in size. The disease is not fatal to the tree, but the appearance of the tar spots alarms some tree owners. A major outbreak in New York about 10 years ago left many maples completely defoliated by mid-August.
Resources:
Diplodia Tip Blight of Two-Needle Pines, The Education Store, Purdue Extension resource center
Boxwood Blight, The Education Store
Disease of Landscape Plants: Cedar Apple and Related Rusts on Landscape Plants, The Education Store
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension – Forestry & Natural Resources (FNR) YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension – FNR YouTube Channel
Find a Certified Arborist, Trees are Good-International Society of Arboriculture (ISA)
Video: Step by Step to Find an Arborist, Trees are Good-International Society of Arboriculture (ISA)
Professional Forester, Indiana Forestry Woodland Owners Association
District Forester, Indiana Department of Natural Resources, 10+ acres
Trees and Storms – The Education Store
Why Is My Tree Dying? – The Education Store
Tree Risk Management – The Education Store
Tree Pruning Essentials, Publication & Video, The Education Store
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – FNR
What are Invasives Species and Why Should I Care?, Got Nature? Blog, Purdue Extension – FNR
Subscribe – Purdue Extension-FNR YouTube Channel
Janna Beckerman, Professor of Plant Pathology
Purdue Department of Botany and Plant Pathology
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
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
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
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
Question: Can I plant grass over soil where a newly removed stump was ground out?
Answer: We generally don’t want to plant new trees or turf immediately over the top of existing stumps in landscapes. The reasoning is a bit complicated but somewhat simple. The stump
location will have limited soil and rooting depth for nutrient uptake and structural stability due to its remaining below ground mass.
The woody debris material created from stump grinding has a high carbon to nitrogen (C:N) ratio. This reduces nitrogen availability for the new tree or grass. Also, there will be significant settling of the ground below the stump as it decays and loses its structural fiber. The soil should be added to replace the below ground roots and stump. It can take several years to fully decompose the stump unless it was ground very deeply or removed with an excavation machine.
The recommendations are adding soil to the stump area, and a little additional soil mounded to compensate for some decay. Plant the grass, preferably sod, however, seed can work, to adequately cover the newly exposed area. Be sure to add slow-release turf fertilizer to compensate for the high C:N ratio that will be robbing nutrition from the newly installed turf. Maintain adequate moisture and look for signs of yellowing, indicating low nitrogen levels.
Also, sprouts may be generated due to the roots acting as energy storage for the tree. Simply treat them with typical lawn herbicide as needed at the label recommended rates.
Resources:
Taking Care of Your Yard: Homeowner’s Essential Guide to Lawns, Trees, Shrubs, and Garden Flowers, The Education Store, Purdue Extension Resource Center
Homeowner Conservation Practices to Protect Water Quality, Purdue Rainscaping, Purdue Extension Resource Center
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Purdue Landscape Report
Lindsey Purcell, Chapter Executive Director
Indiana Arborist Association
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