Purdue University - Extension - Forestry and Natural Resources
Purdue Landscape Report, What is Happening to the Weeping Willows?: While recent temperatures have been moderate in many parts of the state, rainfall has been lacking. (See The Annual Drought Article). There are chasms in the clay of my backyard that will swallow my kids and dogs whole. While I am not truly worried about the safety of my smaller family members, a lot of the plants that are not in shade are stressed. At the Purdue Plant and Pest Diagnostic Laboratory, we have received quite a few calls, emails, and samples about trees in decline. Trees that are already stressed, infected by a pathogen, or are infested by wood-boring insects will be showing their true colors in these drought conditions: chlorosis, leaf loss, and limb dieback.
Willow showing yellowing of older leaves on lower branches.
This month, one group of trees limps along to the top of our list of plants under stress due to lack of water: Willows. Salix spp. are not great landscape trees in general unless planted in locations that retain water. While they grow quickly and can appear beautiful for a number of years, when the soil becomes dry, these trees can very quickly develop limb dieback or cankers. In many cases, cankers become more obvious during these periods of stress because they were already present before the drought stress occurs. Damaged limbs die faster and multiple species of canker-causing fungi have been found to move faster in drought stressed wood of some tree species. We have found the fungi Cytospora, Botryosphaeria, and Colletotrichum associated with cankers on recent branch submissions to the lab.
Thinning of the branches, cracks/splits in the bark, and black lesions on green stems can indicate the presence of a canker which should be pruned out and destroyed, if at all possible. Supplemental irrigation may be required during dry spells for trees that are water loving or, at least, drought intolerant. Fungicides are not effective for these fungal pathogens that live inside the wood, where fungicides can’t penetrate. In most cases larger willow trees will not die because of these problems but they may suffer significant branch loss and may become disfigured. In some cases very young trees or shrub type willows may be killed.
For full article and photos view: What is Happening to the Weeping Willows?
Resources:
Summer Tree Care, Purdue Landscape Report
Drought? Don’t Forget the Trees!, The Education Store, Purdue Extension resource center
Extreme Heat, Purdue Extension – IN-PREPared
Drought Information, Indiana Department of Natural Resources
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Selection for the “Un-natural” Environment, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel
Tree Defect Identification, The Education Store
Tree Wound and Healing, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Surface Root Syndrome, The Education Store
John Bonkowski, Plant Disease Diagnostician
Plant and Pest Diagnostic Laboratory
Starting trees from seed requires knowing the germination requirements for the species you wish to grow. Most native tree seeds require treatments to break seed dormancy before the seed will germinate. These are done naturally by weather cycles, moisture, sunlight and wildlife in the forest environment. When we collect seeds, we will have to simulate these natural events to germinate the seeds successfully.
The Woody Plant Seed Manual, a U.S. Forest Service publication, gives detailed germination and nursery culture instructions by genus and species of trees. With over 450 seeds of woody plants in the United States, this manual continues to be popular both in this country and beyond. Seed data includes approximately 800 species, varieties, and sub-species in 188 genera, considerable more than the 420 species and 140 genera in this edition.
View this general germination guide for some common tree species.
Resources:
Frost Seeding to Establish Wildlife Food Plots & Native Grass and Forb Plantings – YouTube Video
Planting Hardwood Seedlings – The Education Store
Ordering Seedlings from the State Forest Nursery System, Got Nature? – Purdue Extension-FNR
Instructions for Ordering Tree Seedlings – Indiana DNR Division of Forestry
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
National Nursery and Seed Directory – USDA Forest Service
Web Soil Survey – USDA Natural Resources Conservation Service
ID That Tree – YouTube Playlist
Diana Evans, Extension and Web Communication Specialist
Purdue University Department of Forestry and Natural Resources
Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources
Question: I am building a hedge row and am contemplating working with Osage-orange seedlings and planting them. Is this a good choice?
Answer: Osage-orange, (Maclura pomifera) aka hedge, hedge-apple, bodark, bois d’arc and several other common names, is a tree native to parts of Arkansas, Oklahoma, and Texas, but has been planted in every one of the lower 48 states. The reason for that extensive planting was Osage-orange was promoted as the best tree for “living fences”, which were hedgerows planted to enclose or exclude livestock before the use of barbed wire. Osage-orange was also widely panted as a hedge-row and windbreak by the conservation programs of the FDR administration in the 1930’s. You can still encounter some of those old hedgerows on the landscape. It made a good hedgerow because the stems have stout thorns at the base of the leaves and will produce large and dense sprout colonies when cut back or pruned. It produced a living fence described as “horse-high, bull-strong, and pig-tight”.
The wood of Osage-orange was also used for wagon wheel parts, tool handles and fence posts due to its strength and rot-resistance. I have met a few landowners who showed me Osage gate or fence posts they had helped set as a child that were still in good condition 60 or more years later. It is also an excellent firewood, with one of the highest BTU yields of any native tree. Native peoples used straight-grained Osage-orange wood for outstanding bows, thus the French name bois d’arc and the English derivation bodark. Some crafters still seek Osage wood for making traditional bows or for turnings and other decorative items. The wood becomes so hard and dense with drying that it is recommended in most cases to work it green. The yellow-orange fresh wood color gradually ages to a deep reddish brown.
Osage-orange may have had more favorable treatment as a wood for many uses were it not for the tendency of the tree to fork, bend and twist, making straight, long stems uncommon.
The fruit of Osage-orange is where this and the hedge-apple name comes from. Osage-orange is neither a citrus tree nor an apple, but the large, round, green to yellow fruit suggest each to some extent. The interlacing bumps and crevices and the round shape suggest a brain to many, including myself. The closest relatives of Osage-orange are actually the mulberries. The size of this fruit and the limited number of current animals that will use it have prompted some to suggest it was originally eaten and propagated by large, and now extinct, ice-age animals such as the giant ground sloth, mammoth, and mastodon.
Osage-orange has many interesting and sometimes useful characteristics, but it can also become weedy in some situations. It can spread by seed or sprouts into disturbed areas like abandoned fields, farmlands, or grazed areas and out-compete native vegetation. For these reasons, planting new areas to Osage-orange is usually discouraged.
Resources:
You Say Hedge-Apple, I Say Osage Orange!, Indiana Yard and Garden – Purdue Consumer Horticulture.
Osage Orange, The Wood Database
ID That Tree: Osage-Orange, Purdue Extension-FNR’s YouTube playlist
ID That Tree, Purdue Extension-FNR’s YouTube playlist
Windbreaks – Agroforestry for Any Property, Caring for your Woodland, University of Wisconsin-Madison, Extension
The Woody Plant Seed Manual, U.S. Forest Service
Native Trees of the Midwest, The Education Store, Purdue Extension’s resource center
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Woodland Management Moment , Purdue Extension-FNR’s YouTube playlist
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 Resources
The classic and trusted book “Fifty Common Trees of Indiana” by T.E. Shaw was published in 1956 as a user-friendly guide to local species. Nearly 70 years later, the publication has been updated through a joint effort by the Purdue Department of Forestry and Natural Resources, Indiana 4-H, and the Indiana Department of Natural Resources, and reintroduced as “An Introduction to Trees of Indiana.”
The full publication is available for download for $7 in the Purdue Extension Education Store. The field guide helps identify common Indiana woodlot trees.

book, paired with an ID That Tree video from Purdue Extension forester Lenny Farlee to help visualize each species as it stands in the woods. Threats to species health as well as also insight into the wood provided by the species, will be provided through additional resources as well as the Hardwoods of the Central Midwest exhibit of the Purdue Arboretum, if available.
Each week, the Intro to Trees of Indiana web series will offer a sneak peek at one species from the
This week, we introduce River Birch or Betula nigra, which is also known as red birch.
As its name implies, it is found frequently in wet situations. It is often found need waterways and in moist soil areas across the state.
Full article also can be viewed with Purdue Forestry and Natural Resources News: Intro to Trees of Indiana: River Birch
Other Resources:
Birch – Hardwood Lumber and Veneer Series
Fifty Common Trees of Indiana
An Introduction to Trees of Indiana
Native Trees of the Midwest-The Education Store, Purdue Extension’s resource center
Shrubs and Woody Vines of Indiana and the Midwest– The Education Store
ID That Tree– YouTube playlist
Woodland Management Moment-YouTube playlist
Investing in Indiana Woodlands– The Education Store
Forest Improvement Handbook– The Education Store
Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources
Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources
It is official. The Asian needle ant is our newest invasive insect pest and has now become a permanent resident, stinging ant. Two ant specimens taken from a wooded area in southern Indiana by an astute amateur entomologist, who observed their appearance and behavior as ‘out of the ordinary’, was submitted to the Indiana Department of Natural Resources and to the Purdue University Plant and Pest Diagnostic Laboratory for species identification in February, 2022. Both were confirmed to be Formicidae: Brachyponera chinensis, commonly known as the Asian needle ant, not previously recorded from Indiana.
Asian needle ants (ANAs), originally from Eastern Asia (China, Japan, and Korea), were first discovered in the United States in the early 1930s, but only recognized as a pest since 2006. They have been officially established in several states in the U.S. including North Carolina, South Carolina, Alabama and Georgia and, have been anecdotally reported as far north and west as New York, Tennessee and Kentucky.
Note that stings to humans will be moderately painful (potentially causing severe allergic reactions to susceptible individuals) much like fire ant or bee stings, but fortunately because these ants are much less aggressive in protecting their nests, the number of stings per encounter will be less.
The First Report of the Invasive Asian Needle Ant in Indiana pdf provides more details on their identification and biology.
If you want to confirm a sighting of the Asian needle ant please contact the Purdue University Plant and Pest Diagnostic Laboratory at this time. More information will be presented as experts monitor the spread.
Resources:
Thousand Cankers Disease, Indiana Department of Natural Resources
Thousand Cankers Disease: Indiana Walnut Trees Threatened, The Education Store, Purdue Extension’s resource center
Indiana Walnut Council
Spotted lanternfly: Everything You Need to Know in 30 Minutes, Video, Emerald Ash Borer University
Emerald Ash Borer, EAB Information Network
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
Woodland Management Moment: Invasive Species Control Process, Video, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
Invasive Species, Playlist, Purdue Extension – FNR YouTube Channel
What are invasive species and why should I care?, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Report Invasive
Indiana Department of Entomology and Plant Pathology
Tim Gibb, Insect Diagnostician and Extension Specialist
Purdue Department of Entomology
Lawn to Lake Midwest is a great resource as the experts share each month care tips on how to have a healthy lawn all year long while using natural lawn care practices. For the month of May check out the things to watch out for and why testing your soil is important.
You will also find resources for more options for a sustainable lawn:
Resources:
Forest Improvement Handbook, The Education Store
Turfgrass Science, Department of Horticulture & Landscape Architecture
Turfgrass Insect Management, The Education Store
Tree Planting Part 1: Choosing a Tree, Video, The Education Store
Purdue Turf Doctor app for Apple iOS, Apple App Store
Illinois-Indiana Sea Grant (IISG)
In this edition of ID That Tree, meet another member of the hickory family that can found in upland areas, the pignut hickory. This species is identifiable by its five-leaflet compound leaves, its smooth round nut and partially open husk.
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, 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
Pignut Hickory, 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 ID That Tree, meet the ash family, with specific focus on the white ash, which is typically found on higher and drier sites than its cohorts. This species, which is in trouble due to the emerald ash borer, an invasive beetle, features opposite leaf arrangement, compound leaves with seven to nine leaflets, and squatty terminal buds as well as a bud that dips down into the leaf scar, resembling a smiley face. The bark is gray and featured an interlacing network of ridges forming a diamond shape.
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
Emerald Ash Borer (EAB), Purdue Extension-Entomology
A Woodland Management Moment, Playlist, Purdue Extension – 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
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
White Ash, Native Trees of Indiana River Walk, Purdue Fort Wayne
Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources
Purdue Forestry and Natural Resources’ extension efforts over the past two years amidst the COVID-19 pandemic were recognized in the Purdue Extension Specialist Quarterly newsletter.
The transition to virtual content brought expertise across subject matter areas, ranging from forestry and wildlife, to aquatic sciences and entomology, to the masses in the form of several video series which collectively earned nearly 150,000 views.
The FNR Extension team included: Jay Beugly, Jarred Brooke, Nick Burgmeier, Barny Dunning, Diana Evans, Lenny Farlee, Jason Hoverman, Liz Jackson, Brian MacGowan, Patrick McGovern, Wendy Mayer, Charlotte Owings, Lindsey Purcell, Bee Redfield, Shelby Royal, Bob Rode, Kara Salazar, Mike Saunders, Amy Shambach, Rod Williams, Mitch Zischke, as well as frequent Entomology contributors: Elizabeth Barnes, Cliff Sadof.
The feature in the fourth quarter newsletter begins:
“While Covid caused limitations on travel and in-person events nationwide, across Indiana, many were spending more time in outdoor recreational activities, hiking, bird-watching, hunting and fishing, or managing natural resources properties. Adjusting to the pandemic, the FNR team created an innovative and team-oriented instruction approach through skill-building in video production with coordinated connection and cross-promotion of resources.
“Forestry and Natural Resources (FNR) faculty, specialists, staff, and students, with invited partners across research and Extension, delivered 45-minute Ask an Expert Facebook Live programs for 35 weeks. Programs covered many FNR specialties: Animals & Insects (bats, bird, cicadas, coyotes, deer, fish, frogs, hellbenders, moles, pollinators, salamanders, snakes, toads, turtles, and wood pests); Plants & Ecosystems (invasive plant species, hardwood ecosystems, native grasses for wildlife, conservation tree planting, rainscaping, fall food plots, and selecting, planting and inspecting trees); and Management & Operations (prescribed fires, aquatic plant and pond management, and fish and wildlife management).
Resources:
Ask An Expert Playlist, Purdue Extension – Forestry and Natural Resources (FNR) YouTube Channel
ID That Tree Playlist, Purdue Extension – FNR YouTube Channel
A Woodland Management Moment Playlist, Purdue Extension – FNR YouTube Channel
Wildlife Habitat Hint Playlist, Purdue Extension – FNR YouTube Channel
Subscribe to the Purdue Extension – Forestry and Natural Resources YouTube Channel
Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources
Diana Evans, Extension and Web Communication Specialist
Purdue University Department of Forestry and Natural Resources
This week on ID That Tree, Purdue Extension forester Lenny Farlee introduces you to a non-native conifer that can be found throughout the state, the Red Pine. This species, which enjoys sandy soil, is identifiable by its small, egg-shaped cones, as well as tufts of needle pairs, which can be quite brittle, and orange/reddish bark. Learn more 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, 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, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources