Got Nature? Blog

Purdue Landscape Report: Pseudomonas syringae pv. syringae is an opportunistic bacterial pathogen that attacks a diversity of woody ornamental plants. The bacteria cause flower blights, cankers, shoot blights, and diebacks.

Symptoms
Symptoms often begin as expanding leaf spots. On lilac and viburnum, small spots expand to irregularly shaped brown lesions with yellow halos (Fig. 1). For most other hosts (cherry, pear, basswood, dogwood, hydrangea, high bush-cranberry, mountain-ash), infected leaves turn reddish brown or black and usually remain on the branch after they die (Fig. 2). As the bacteria spread into woody tissue, dark, sunken sections of the stem (cankers) expand, working their way back toward the trunk from infected leaves and flowers. Leaves attached to a cankered branch will wilt while the tip of the affected branch curls and droops like a shepherd’s crook (Fig. 3). Cloudy droplets of sticky fluid (ooze) may accumulate on leaf tips, leaf surfaces, stems, and even infected fruit.

Image of infected flowers result in blossom blast.
Figure 2. Infected flowers result in blossom blast. The continued growth of the bacteria can result in cankering and blight. Photo by George Sundin.

Life Cycle
The bacteria overwinter and persist in cankers, along with asymptomatic bud and twig tissue. In presence of water and warming temperatures, bacteria multiply and may ooze from infected tissue. Wind-driven rain, insect, or mechanical pruning spread Pseudomonas. Bacteria enter the plant through flowers or injury.

Management
All bacterial pathogens, including Pseudomonas, invade flowers or wounded tissue. To prevent or minimize the risk of infection:

• Use disease-free plants and budwood.
• Prune in the late winter/early spring.
• When pruning, do not mix pruning to shape woody ornamentals with pruning to manage disease.
• When pruning to remove infected shoots, be sure to disinfect shears between plants.
• Minimize overhead irrigation when possible to minimize splashing and pathogen spread.
• Avoid over-fertilization practices that drive excess succulent growth.
  

  Figure 3. Bacterial blight is a common scourge to common lilac. Using resistant varieties is the best way to protect against the disease. Photo by Janna Beckerman.

• Avoid late season fertilization practices that prevent plants from achieving timely dormancy and promote freeze damage and/or winter injury (Fig. 4).
• Choose zone appropriate plants to avoid freeze damage and/or winter injury.
• Choose disease resistant plants, when available. The following lilac varieties were found to be resistant over a four-year trial: Donald Wyman, Royalty, Superba, Miss Kim, Edmund Boisier, Victor Lemoine, Dwarf Korean, Mme. Antoine Buchner Isabella, Sensation, Anna Amhof, Krasavitska Moskvy, Michael Buchner, and Alphonse Lavallée.

Foliar sprays of some copper-based bactericides (e.g., Camelot, Kocide, and Nu-Cop) were found to reduce disease incidence in trials on lilac (Vey and Palmer, 2018). Avoid using copper under cool, humid conditions to reduce the risk of phytotoxicity and damaging plants. Copper resistant populations of Pseudomonas syringae have been reported in other crops (vegetables, stone fruit). Products containing acibenzolar have provided inconsistent control in multiple trials but is labeled for use. Use of quaternary-ammonium disinfestants (KleenGrow) have been found to reduce bacterial populations and disease incidence and should be considered as part of any rotation with copper products. Due to the diversity of copper products, be sure to test for phytotoxicity issues prior to large scale treatment of crops.

To view this 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
Purdue Landscape Report Facebook Page
Find an Arborist website, Trees are Good, International Society of Arboriculture (ISA)
Phytophthora Diseases in Ornamentals, The Education Store, Purdue Extension’s resource center
Root Rot in Landscape Plants, The Education Store
Symptoms and Signs for Plant Problem Diagnosis, The Education Store
Tree Defect Identification, The Education Store
Tree Pruning Essentials, Publication & Video, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, Purdue University Press
Tree Risk Management – Got Nature? Blog, Purdue Extension – FNR
Equipment Damage to Trees, Got Nature? Blog
Tree wounds and healing, Got Nature? Blog
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Southwest Damage, Scalding, or Frost Cracking – Landscape Report
Subscribe to Purdue Extension-FNR YouTube Channel

Janna Beckerman, Professor of Plant Pathology
Purdue Department of Botany

---

This exotic invasive tree species is commonly found in Indiana landscape, callery pear. Callery pear has been planted as an ornamental tree in the midwest for decades. The original selection bradford pear was actually infertile and would not spread from seed but additional varieties have been planted and have crossed with the original Bradford and those are producing fertile seed. Find out how the seed spreads and what we can do to help our forest.

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 (Report Invasives)
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

---

Purdue Landscape Report: Asian jumping worms, a group of invasive earthworms, have gained a significant amount of media attention in the last several weeks, and for good reason.  Unlike the nightcrawlers and other earthworms we know, Asian jumping worms do not improve soil health to the benefit of plants.  Instead, jumping worms (also called crazy worms, snake worms, or ‘Alabama jumpers’) almost completely strip nutrients out of soil, altering the soil structure and severely impairing the ability to develop many kinds of plants. After they are done with an area, Asian jumping worms leave behind soil that has a texture similar to that of coffee grounds and very low nutritional value. On top of this, Asian jumping worms are capable of reproducing asexually, allowing their population to grow very rapidly and making them an invasive species of some concern.

Identification
The good news is that Asian jumping worms are not well-suited to Indiana’s environment.  They aren’t capable of surviving winters in any life stage except as an egg, meaning their activity periods are limited to late June to the first hard frost of the year.  If you see worms outside of this period, it’s highly unlikely an Asian jumping worm.  There are also a few traits the worms have that you can use to visually confirm their identity.  First off, Asian jumping worms are accurately named; when handled, they writhe and thrash similar to snakes, setting them apart from common earthworms and nightcrawlers.  Jumping worms also tend to have drier skin that has an almost iridescent appearance, as compared to the slimy, moist texture of the beneficial earthworms we need for good soil health.  The most consistent feature is an organ known as the clitellum, or the reproductive organs of worms.  On common earthworms, this looks like a saddle-shape that partially covers several segments, is normally reddish-brown, and is raised off the surface of the body.  On an Asian jumping worm, however, the clitellum is indistinguishable from other segments, save for their pale, milky color.

To view this 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
Purdue Landscape Report Facebook Page
Gardeners Asked to be Vigilant This Spring for Invasive Jumping Worm, Purdue Extension – FNR Got Nature? Blog
Fall webworms: Should you manage them?, Purdue Landscape Report
Mimosa Webworm, The Education Store, Purdue Extension resource center
Sod Webworms, Turf Science at Purdue University
Bagworm caterpillars are out feeding, be ready to spray your trees, Purdue Extension Forestry & Natural Resources (FNR) Got Nature? Blog
Purdue Plant Doctor App Suite, Purdue Extension-Entomology
Landscape & Ornamentals: Bagworms, The Education Store
What are invasive species and why should I care? (How to report invasives.), Purdue Extension – FNR Got Nature? Blog
Indiana Invasive Species Council
Ask An Expert, Purdue Extension-Forestry & Natural Resources

Bob Bruner, Exotic Forest Pest Specialist
Purdue Department of Entomology

---

The Natural Resources University podcast group received the gold award in the podcast or radio category from the Association of Natural Resource Extension Professionals (ANREP). The NRU podcast group includes the Habitat University podcast co-hosted by Purdue Extension wildlife specialist Jarred Brooke and Adam Janke, an extension wildlife specialist at Iowa State University.

“Receiving the ANREP Gold Award is an honor,” Brooke said. “What started as casual conversations amongst colleagues about creating science-based natural resources podcasts has blossomed into a podcast network with multiple unique podcasts and over 100 episodes. This collaboration has been a great avenue to get up-to-date science about natural resource management into landowners and managers’ hands (and ears).”

The NRU podcast group initially began with four science-based podcasts covering different aspects of natural resource management: Deer University, Pond University, Fire University and Habitat University.

Deer University, which is hosted by Dr. Bronson Strickland and Steve Demarais, focuses on the science of deer, including deer ecology, biology and management.

Pond University, which was co-hosted by FNR’s Mitch Zischke and Megan Gunn before ending its 11-episode run in August 2021, covered topics from pond habitat to fish stocking, vegetation control and pond construction.

Fire University, which is hosted by Dr. Marcus Lashley, covers the gamut of the latest research in fire ecology and how it relates to management of wildlife and plant communities.

Habitat University, hosted by Brooke and Janke, discusses the science behind wildlife habitat management and how landowners and manages can use different habitat management practices to improve their land for wildlife.

New to the NRU family in 2022-2023 are:

• Wild Turkey Science – Dr. Marcus Lashley and Dr. Will Gulsby bring you the latest research on wild turkey ecology and management
• Timber University – Dr. Brady Self and Dr. Shaun Tanger cover the latest research in timber management.
• Working Wild University – Dr. Alex Few and Dr. Jared Beaver immerse the listener in stories at the heart of the struggle to sustain productive, resilient and connect rural landscapes and communities.
• Fish University – Dr. Wes Neal covers the latest research in fish management from the small pond to the vast ocean.

The series housed within the NRU network aim to deliver expert-based knowledge for their corresponding genre of natural resource management. The network is a partnership between the extension services at several land-grant university, including Mississippi State Extension Service, University of Florida Extension, Iowa State University Extension and Outreach and Purdue Extension. Funding for the project comes from the Renewable Resources Extension Act.

The Natural Resources University podcasts are available through the individual podcast websites, through the NRU podcast main hub or wherever podcasts are available to download.

For full article and more photos view Purdue Forestry and Natural Resources News & Stories: Natural Resources University Podcasts Earn ANREP Gold Award .

More Resources:
Ask an Expert: Pond Management, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Pond Management: Managing Fish Populations, The Education Store, Purdue Extension’s resource center
Yellow Perch Farmed Fish Fact Sheet, The Education Store
Frogs and Toads of Indiana, The Education Store
Snakes and Lizards of Indiana, The Education Store
Forest Improvement Handbook, The Education Store
Frost Seeding Native Grasses and Forbs with a Drone (UAV), Purdue Extension-FNR
Hardwood Ecosystem Experiment – Wildlife Responses to Timber Harvesting, The Education Store
Invasive Plants: Impact on Environment and People, The Education Store
Ask the Expert: Turtles and Snakes video, Got Nature? post
ID That Tree, Purdue Extension-FNR YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources

Jarred Brooke, Wildlife Extension Specialist
Purdue 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.

Each week, the Intro to Trees of Indiana web series will offer a sneak peek at one species from the 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.

This week, we meet the Jack pine, or Pinus banksiana.

This conifer, also known as scrub pine, has clusters of two dark green needles, which are one to one and a half inches long, noticeably curved or arched like a bow and slightly twisted.

Bark on the jack pine is dark to medium gray, thin and flaky when young and features thick plates in older trees. This tree growth irregularly and can produce between one and three whorls of side branches annually. It tends to have a much lighter crown than white pine or the spruces.

The cones of jack pine are one to three inches long and remain closed while on the tree unless disturbed by a heat event such as fire. The cones may also be curved and twisted into many irregular shapes and tend to stay on the tree for many years.

For full article with additional photos view: Intro to Trees of Indiana: Jack Pine, Forestry and Natural Resources’ News.

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.

Other Resources:
ID That Tree: Jack Pine
Morton Arboretum: Jack Pine
Jack Pine, Native Trees of Indiana River Walk, Purdue Fort Wayne
Borers of Pines and Other Needle Bearing Evergreens in Landscapes, The Education Store, Purdue Extension’s resource center
Managing the Zimmerman Pine Moth, The Education Store
Purdue Arboretum Explorer
The Woody Plant Seed Manual, U.S. Forest Service
Native Trees of the Midwest, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources

Lenny Farlee, Extension Forester
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.

Each week, the Intro to Trees of Indiana web series will offer a sneak peek at one species from the 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.

This week, we meet the scotch pine, or Pinus sylvestris, which is not native to Indiana, but has been widely planted in the state for Christmas tree production.

This conifer, also known as Scots pine, has clusters of two blue green or yellow green needles, which are one to three inches long and do not break when bent.

Bark on the scotch pine is light gray on the outside and orange in color on the inner bark, but it is not flaky like red pine. Bark on the lower end of the trunk is dark and blocky, while the upper bark is more orange.

On the tree, cones are cylindrical and pointed at the ends, approximately three inches long and do not have spines at the end of the scales. Cones become more egg shaped as the scales begin to open up once off the tree.

Scotch pine, which grows to between 25 and 60 feet tall, is typically found on acidic, moist, well-drained soil. It prefers full sun and has some drought tolerance. The species’ native range is Scotland, Scandinavia, northern Europe and northern Asia. According to the U.S. Forest Service database, It has been introduced across the United States and Canada and is naturalized in the Northeast and in the Great Lakes states.

For full article with additional photos view: Intro to Trees of Indiana: Scotch Pine, Forestry and Natural Resources’ News.

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.

Other Resources:
ID That Tree: Scotch Pine
Morton Arboretum: Scotch Pine
A Choose-and-Cut Pine and Fir Christmas Tree Case Study
Diplodia Tip Blight of Two-Needle Pines, The Education Store, Purdue Extension’s resource center
Borers of Pines and Other Needle Bearing Evergreens in Landscapes, The Education Store
America’s Least Wanted Wood-Borers, Japanese Pine Sawyer, The Education Store
Managing the Zimmerman Pine Moth, The Education Store
Purdue Arboretum Explorer
The Woody Plant Seed Manual, U.S. Forest Service
Native Trees of the Midwest, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources

Lenny Farlee, Extension Forester
Purdue University Department of Forestry and Natural Resources

---

The Niehaus’ tree farm encompasses 182 acres in Perry and Dubois counties in southern Indiana. The land has been in their family since Dave Niehaus’ grandparents bought it soon after they married in 1909. Back then, only 100 or so acres of the property were forest; the remaining 80 acres comprised open land.

Niehaus’ grandparents built a house on the farm in 1918. In 1931, his grandfather died in a horse accident, leaving his grandmother to raise their nine children. Dave’s father, the oldest, was 19 at the time.

The children grew up and moved on, but Niehaus’ grandmother would continue living there for the remainder of her life. Young Dave grew up in Saint Meinrad, about six miles away. “I spent a lot of time up there, in the forest,” he says. “The fields then were in the Soil Bank program (now the Conservation Reserve Program) because about 40 acres of the open ground was in the flood plain, so they were used to losing their crops, and losing their soil down in the bottoms. In the CRP ground, once a year you’d have to mow all of that down. Dad had a little 8N Ford tractor with a side mower on there, and I mowed all that down and just spent time with Grandma up there.”

Niehaus’ older brother bought the property in 1969. When he decided to sell, Dave stepped up to purchase it in 2005.  “It’s our roots,” he explains. “I didn’t want it divided up.”

Ten years earlier, he’d asked his brother for some land so he could try his hand at planting trees. Niehaus was an Army veteran and a carpenter; he didn’t know much about forestry, but he wanted to learn. He started in 1995 on a four-acre horse pasture with 16 5-gallon buckets of acorns he’d raked up in a city park. He rigged up a PVC pipe that dug a trench in the subsoil as he dropped the acorns through a funnel into the pipe, planting them in rows across the field.

The following spring, not a single white oak came up. “My brother just laughed and said, ‘You got a lot of fat mice running around up there,” Niehaus recalls.

The following fall, he enlisted the help of Dr. Jim Wichman with the Indiana Department of Natural Resources, Division of Forestry Nursery Section. Niehaus started one bucket of acorns in his garden, where he could better protect them from predators and mold. He experimented with coverage, noting that germination under peat moss far exceeded that of pine needles and dirt. He then hand-transplanted the seedlings to rows on the open land — a second, and more successful, try at growing a forest.

Over the next three years, Niehaus cultivated enough seedlings to hand plant the four acres. He expanded his sights.

One year he got 500 seedlings from the state nursery and in the course of planting them, credits his then 10-year-old daughter with an important lesson. “She said, ‘Dad, this is going to look funny when this grows up… When you go into a forest, the trees are spaced here and there. And these are all going to be in a row.’ And I said, ‘Andrea, you just got the vision.’ So that’s what it is now.”

After he bought the property in 2005, Niehaus signed on for a class at the Southern Indiana Purdue Agricultural Center in nearby Dubois, Indiana, Forest Management for the Private Woodland Owner. Extension Forester Ron Rathfon led the eight-week course.

“I wanted to know a little more about forestry,” Niehaus says. “I wanted to be a good steward of the property.”

Rathfon has been helping residents manage their woodlands for 30 years, along with the Purdue Forestry and Natural Resources Extension team and public and private resource professionals who offer classroom and field instruction. “Ron makes the class interesting, and he makes it fun,” Niehaus says.

His main takeaways from the course were in tree identification and forest biology. “If you want to manage your forest to get it to grow back to be oak trees, you have to be able to recognize the different species of trees at different ages,” Niehaus says.

For full article with additional photos view: Creating A Woodland Legacy: Dave and Carol Niehaus, Extension News and Stories

Resources
Hardwood Ecosystem Experiment – Wildlife Responses to Timber Harvesting, The Education Store, Purdue Extension resource center
Forest Improvement Handbook, The Education Store
Invasive plants: impact on environment and people, The Education Store
Managing Your Woods for White-Tailed Deer, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Forest Management for Reptiles and Amphibians: A Technical Guide for the Midwest, The Education Store
Breeding Birds and Forest Management: the Hardwood Ecosystem Experiment and the Central Hardwoods Region, The Education Store
Native Trees of the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist
Subscribe: Deer, Forest Management, ID That Tree, Woodland Management Moment, Invasive Species and many other topic video playlists, Purdue Extension-Forestry and Natural Resources YouTube Channel

Ron Rathfon, Regional Extension Forester
Purdue University Department of Forestry and Natural Resources

Purdue Extension

---

Purdue Landscape Report: There have been a number of samples we have received at the PPDL in recent weeks that bear similar problems worth noting. It is still relatively early for significant in-season disease development due to how cold it has been, although we have certainly had enough rainfall to encourage fungal growth. We have received multiple samples of spruce and boxwood which will be covered.

Since the start of the year, we have been received spruce samples showing needle thinning, browning, and loss in the lower canopy (Fig 1, 2, 3). If I said these are Colorado Blue Spruce, we could call it Rhizosphaera and maybe call it a day, however, these samples are primarily from other species of spruce. An important thing to remember when it comes to evergreen conifers is that it takes time for symptoms to develop, whether due to disease or to abiotic factors. The majority of these branches lacked any discoloration within, suggesting that there was no infection and that the limbs were still living.

Last year, we had drought conditions during the summer throughout large parts of the state leading into the fall with below average precipitation (Fig 4). Since evergreen plants hold onto their foliage through the winter, desiccation can occur since they are still losing water to the air, especially when it is dry and windy. If these plants are not getting enough water going into winter, there is greater risk of winter injury or burn and needles may turn brown, especially near branch tips (exposed areas).

Irrigation during periods of hot and dry weather will mitigate drought stress, but irrigation may still be necessary in the fall to avoid needle desiccation. What about when trees of the same age, on the same property are showing different levels of severity or one tree is perfectly fine while the next is toast?

I think it is important to remember each tree is an individual. We may see similar patterns in the landscape across the same tree species when stress is caused by environmental effects, but if the overall health of that tree when it was first planted, the amount of love and care, and the site conditions (soil, light, general water levels) are different, then the trees may have vastly different reactions to stress. Determining this 5 years after planting can be difficult for someone just walking into the situation, or when dealing with 30ft tall trees, but it is something we have to keep in mind.

For more images and full article view: Early Season Samples: Spruce Needle Loss and Boxwood Leaf Spots

Subscribe and receive the newsletter: Purdue Landscape Report Newsletter.

Resources:
The Purdue Landscape Report
Purdue Landscape Report Facebook Page
Find an Arborist website, Trees are Good, International Society of Arboriculture (ISA)
Equipment Damage to Trees, Got Nature? Blog
Tree wounds and healing, Got Nature? Blog
Tree Defect Identification, The Education Store, Purdue Extension resource center
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
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Subscribe to Purdue Extension-FNR YouTube Channel

John Bonkowski, Plant Disease Diagnostician
Departments of Botany & Plant Pathology

---

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.

Each week, the Intro to Trees of Indiana web series will offer a sneak peek at one species from the 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.

This week, we meet the red pine, or Pinus resinosa, which is not native to Indiana, but has been planted widely across the state.

This conifer has clusters of two slender, flexible, green or yellow green needles, which are four to six inches long. If the needles are bent, they will break cleanly, unlike that of ornamentally planted Austrian pine. The long needles cause a very tufted look to the tree canopy.

Bark on the red pine is scaly and red-orange in color in younger trees and platy and reddish brown in older trees. Cones are egg-shaped, approximately two inches long and have smooth scales.

Red pine tends to be very, straight and tall, growing to between 50 and 80 feet tall. This species, which can be as tall as 200 feet, is typically found on sandy, well-drained soils with low pH and full sun. The natural range of the red pine is the northeastern United States and southern Canada near the Great Lakes and St. Lawrence River. The species can be found as far west as Minnesota and into Manitoba. It can be found dipping south into Wisconsin, Illinois, Michigan, West Virginia and Pennsylvania.

For full article with additional photos view: Intro to IN Trees: Red Pine, Forestry and Natural Resources’ News.

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.

Other Resources:
ID That Tree: Red Pine
Morton Arboretum: Red Pine
Diplodia Tip Blight of Two-Needle Pines, The Education Store, Purdue Extension’s resource center
Borers of Pines and Other Needle Bearing Evergreens in Landscapes, The Education Store
Native Trees of the Midwest, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
Purdue Arboretum Explorer
The Woody Plant Seed Manual, U.S. Forest Service
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources

Lenny Farlee, Extension Forester
Purdue University Department of Forestry and Natural Resources

---

 

Purdue Landscape Report: Remember the pre-Christmas freeze? What about the extremely long fall? The Midwest experienced above-average temperatures through most of the winter, but those extremely cold temps in late December made for more than a few pipes to freeze in the southern part of the Midwest. The dichotomy in weather patterns over the last several years has been mind-boggling. We’ve gone from flooding to drought in most recent growing seasons, to the extremes in temperatures this winter. Though it’s an inconvenience for us, plants don’t have the option of heated seats or umbrellas, thus stress or death can occur in these extremes.

East of the Mississippi River, the 2022-2023 winter has been significantly milder than average, based on past climate models (Fig. 1).  We don’t typically have cold injury in late December, but drastic changes in temperatures can cause pernicious effects on plant health.  The entire state of Indiana had the drastic changes in temperature December 22-27, 2022 (Table 1).

There’s on-going evidence of damage across the Midwest from the late/long fall and extreme cold that was experienced in mid-late December.  We’ve observed some perennial evergreens, i.e., American holly, Meserve holly (Fig. 2), and skip laurel (Fig. 3), damaged or killed during this winter, especially in the southern parts of the Midwest. In addition, some deciduous trees have significant bark cracking (Fig. 4).  Though these plants are hardy well below the temperatures that were experienced, the maximum dormancy wasn’t yet reached by plants due to the warm temperatures so late into the winter season.

There’s on-going evidence of damage across the Midwest from the late/long fall and extreme cold that was experienced in mid-late December.  We’ve observed some perennial evergreens, i.e., American holly, Meserve holly (Fig. 2), and skip laurel (Fig. 3), damaged or killed during this winter, especially in the southern parts of the Midwest. In addition, some deciduous trees have significant bark cracking (Fig. 4).  Though these plants are hardy well below the temperatures that were experienced, the maximum dormancy wasn’t yet reached by plants due to the warm temperatures so late into the winter season.

Plants survive through the winter by entering a phase of dormancy in which the plant is in a state of suspended animation.  The dormancy process in plants is a complicated series of internal events caused by external events, that allow perennial plants to protect themselves during environmental changes, such as winter.

For more images and full article view: Cold Injury During a Very Mild Winter?

Resources:
The Purdue Landscape Report
Purdue Landscape Report Facebook Page
Fall webworms: Should you manage them, Got Nature? Blog
Purdue Landscape Report Team Begins New Virtual Series, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources (FNR)
Tree wounds and healing, Got Nature? Blog
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
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Subscribe to Purdue Extension-Forestry & Natural Resources (FNR) YouTube Channel

Kyle Daniel, Commercial Landscape and Nursery Crops Extension Specialist
Purdue Horticulture & Landscape Architecture

---