Got Nature? Blog

Purdue Landscape Report: Tubakia leaf spot, caused by the fungus Tubakia, is the disease we find more commonly on oak than any other. Throughout the world, there are 11 species of Tubakia known to infect oak, with Tubakia dryina (previously known as Actinopelte dryina) being the most commonly encountered species in our landscapes. Apple, ash, black gum, chestnut, elm, maple, and redbud are all reported as hosts of Tubakia species, but oaks are the most frequently and severely affected. Among the oaks, the red oak group, specifically red, pin, and black oaks, are reported to be more susceptible to infection compared to those in the white oak group.

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Figure 2: Oak leaf with circular shaped Tubakia leaf spots along with extensive veinal necrosis.

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Figure 1: Oak leaf with irregularly shaped Tubakia leaf spots and veinal necrosis.

Leaf spots appear in mid to late summer (July –August) as small circular to irregular tan, red-brown, to dark brown spots (Figure 1, 2) that expand to approximately the size of a dime overtime, but can coalesce, forming large areas of necrotic tissue (Figure 3) . When a spot reaches a leaf vein it expands very quickly, causing a necrotic streak along the vein, and can cause blighting of most of the leaf (Figure 4, 5). Trees under stress from other causes will frequently exhibit more severe leaf spotting compared to healthier trees. Premature defoliation can occur in these situations.
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Figure 3: Marginal blighting due to coalescing spots and veinal necrosis.

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Figure 5: Blighting of large leaf area caused by veinal infection by Tubakia.

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Figure 4: Typical Tubakia leaf spot symptoms illustrating how the fungus spreads along leaf veins.

The pathogen produces conidia within shield shaped structures called pycniothyria (Figure 6) which can be found on both the top or bottom surface of the leaf and along veins (Figure 7). These structures are very small and can only be seen with a 40x or stronger hand lens. The fungus overwinters on fallen leaves and on dead stems which act as the source of inoculum for the next year. During early spring, spores are spread by wind and water splash dispersal (rain) to healthy new foliage. However, it takes time for symptoms to develop throughout the season, depending on tree stress and environmental conditions (warm wet weather favors spread).
For full article view: Purdue Landscape Report, Purdue Landscape Report.

Recources
Diseases of Landscape Plants: Leaf Diseases, The Education Store, Purdue Extension resource center
Consumer Horticulture: Fertilizing Woody Plants, The Education Store
Tree Disease; Oak Wilt in Indiana, The Education Store
Diseases of Soybean: Frogeye Leaf Spot, The Education Store
Bur Oak, Purdue Arboretum Explorer
Bur Oak, Native Trees of Indiana River Walk, Purdue Fort Wayne
Find an Arborist, TreesAreGood.org

John Bonkowski, Plant Disease Diagnostician
Purdue Department of Botany and Plant Pathology

Tom C Creswell, Clinical Engagement Professor – PPDL
Purdue Department of Botany and Plant Pathology


Join Purdue Extension forester Lenny Farlee and Dr. Carrie Pike, a forest regeneration specialist with the USDA Forest Service, as they share about conservation tree planting, what species are available to plant, where to get them and more.

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

Resources
Find An Indiana Forester Website
Reforestation, Nurseries and Genetics Resources Website (RNGR.NET)
A Nursery Guide for the Production of Bareroot Hardwood Seedlings, RNGR.NET
Landowner Information, Hardwood Tree Improvement Regeneration Center (HTIRC)
Ask An Expert, Playlist, Purdue Extension – Forestry and Natural Resources Youtube channel
A Woodland Management Moment, Playlist
Ask An Expert: Tree Inspection, Video
Planting Forest Trees and Shrubs in Indiana, The Education Store, Purdue Extension resource center
Tree Appraisal and the Value of Trees, 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 Resource


In this special fall color edition of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to this red beauty, the winged sumac. This species, found in southern Indiana, is recognizable by opposite leaf arrangement, compound leaves with a unique miniature leaf at the end of the stem, as well as drooping clusters of red fruit.

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

Resources
Winged Sumac, Purdue Arboretum Explorer
Fall Color Pigments, Video,  Purdue Extension – Forestry and Natural Resources Youtube Channel
ID That Tree, Playlist
A Woodland Management Moment, Playlist
Investing in Indiana Woodlands, The Education Store, Purdue Extension resource center
Forest Improvement Handbook, The Education Store

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


leaningTrees

Leaning trees can be a risk to neighboring property owners.

Purdue Landscape Report: I hear this complaint or issue more frequently, “what can I do about the neighbor’s tree?” or “my neighbor just butchered my tree!”.  Often, we see issues with a neighboring tree that may threaten safety or appears to be an elevated risk.  For example, from the view of your window, you see your neighbor’s tree dropping dead branches all over your driveway. Or, you can’t see a favorable view at all because of that tree or unruly hedge. Or you are certain that the neighbor’s tree will eventually fall onto your garage.

Before you take any action, establish ownership of the tree, and find out if you have rights to work on the offending vegetation. Otherwise, it can land you into a contentious legal situation.

Some questions to consider include:

When tree limbs or even the trunk of the tree crosses property line, are you within your rights to prune or remove it?

propertyBoundry

Check with local government websites for property maps which can help identify boundaries.

Boundary laws vary with every state. Often the boundary lines are uncertain or assumed based on local information. However, in contentious situations that may result in major modifications to a tree, it is advised to get a survey to establish exactly who owns the tree.

 

Rights are determined by who owns the tree. Check with your town, city, county and state municipalities for regulations about trees and property lines. The rights and responsibility for care and maintenance of trees are assigned to its owner, and ownership is determined by the location of the tree’s trunk. If the trunk is located entirely on the neighbor’s land even if its limbs or branches overhang onto your land, the neighbor is the tree’s owner. The neighbor has the sole right to preserve the tree or cut it down. This is true regardless of the neighbor’s motivation or the impact the tree removal would have on your land.

professionalArboristHelp

An ISA certified arborist can provide mitigation options that are best for the tree and helpful for the tree owner.

It is always best practice and considerate to first ask your neighbor if you can arrange to have it removed or pruned. They might actually appreciate it.

When tree work is required to remove or prune the tree and neighbor conflict exists, have a qualified tree care provider determine the work specifications on exactly how the tree issue should be mitigated. It is usually a bit more complex than simply stating, “cut limbs back to property line.” The work order must reference the ANSI A300 tree pruning standards to assure the procedures being proposed take into consideration the tree’s future health. Ensure that your tree care provider has a copy of their current liability insurance policy on hand. Check their references as well, not all tree care companies are guaranteed to provide the best results for you or your tree.

The best advice is to hire a tree care professional with the experience, expertise, and equipment to assess and safely prune, remove or otherwise care for your or your neighbors’ trees. Search for a tree care provider in your area. Also, consider hiring an ISA Certified Arborist which can be found here.

According to most attorneys, open-minded communications with the neighbor can result in an acceptable resolution for any situation. This will help to avoid contentious, expensive, time consuming, and unpredictable lawsuits.

Resources
Find Qualified Tree Care, Tree Care Industry Association
Find An Arborist, Trees are Good
Tree Pruning Essentials, video and publication, The Education Store, Purdue Extension Forestry and Natural Resources
Construction and Trees: Guidelines for Protection, The Education Store
Question: Can tree roots cause damage to a home’s foundation?, Got Nature? Blog, Purdue Extension – Forestry and Natural

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources


In this special fall color edition of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to the range of colors produced by the sugar maple.

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

Resources
Hard or Sugar Maple, The Education Store, Purdue Extension – Forestry and Natural Resources
Sugar Maple, Purdue Arboretum Explorer
Sugar Maple, Native Trees of Indiana River Walk, Purdue – Fort Wayne
Fall Color Pigments, Video,  Purdue Extension – Forestry and Natural Resources Youtube Channel
ID That Tree, Playlist
A Woodland Management Moment, 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 Resource


The Purdue Landscape Report, a blog which provides science-based, timely information regarding Midwest landscapes to commercial growers, garden centers, landscapers, arborists and the general public, was recognized with the Extension Division Education Materials Award for Outstanding Blog at the American Society of Horticultural Science convention in August.

The Purdue Landscape Report is a collaborative effort between Purdue Extension specialists and diagnosticians in the areas of horticulture, entomology, plant pathology, urban forestry and turf science. Articles cover everything from tree maintenance to pest and disease problems and management to plant selection.

“Our Purdue Green Industry Team brings together many disciplines and expertise for the industry and homeowners as well as any other university in the country,” Nursey and Landscape Outreach Specialist Kyle Daniel said. “The research and outreach efforts of each member of the team contributes to helping the industry be more sustainable, efficient, environmentally conscious, and profitable. The Purdue Landscape Report is one way that we present science-based information to our stakeholders around the state. In addition to this information being distributed locally, there are many subscribers from across the country.”

The PLR team includes:

  • PurdueLandscapeReportAwardASHSKyle Daniel – Nursey and Landscape Outreach Specialist, Purdue Horticulture and Landscape Architecture
  • Rosie Lerner – Extension Consumer Horticulturist, Purdue Horticulture and Landscape Architecture
  • Cliff Sadof – Professor, Entomology Extension Specialist
  • Tom Creswell – Clinical Engagement Professor, Director of the Plant & Pest Diagnostic Laboratory; Purdue Botany and Plant Pathology
  • Janna Beckerman – Professor of Botany and Plant Pathology
  • John Bonkowski – Clerk, Purdue Botany and Plant Pathology
  • Lindsey Purcell – Purdue Extension urban forester, Purdue Forestry and Natural Resources
  • Gail Ruhl – Visiting Scholar, Purdue Biological Sciences
  • Elizabeth Barnes – Exotic Forest Pest Educator, Purdue Entomology
  • Todd Abrahamson – Purdue Plant & Pest Diagnostic Lab Secretary
  • Lori Jolly-Brown – Extension Events and Communications Coordinator, Purdue Horticulture and Landscape Architecture
  • Kirby Kalbaugh – Application and Systems Administrator, Purdue Horticulture and Landscape Architecture

Since launching in February 2018, the Purdue Landscape Report has included more than 144 articles. The website boasted more than 75,000 unique article downloads in 2019. PLR is also sent out in a bi-weekly email newsletter to more than 4,000 subscribers nationwide. The blog has brought in 137,000 unique visitors thus far in 2020.

In August, the Purdue Landscape Report staff also began a live, virtual series every other Wednesday, which addresses articles and hot topics. In just two months, that series has had more than 1,100 views.

Resources
Purdue Landscape Report Team Begins New Virtual Series, Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
The Purdue Landscape Report Issues, Purdue Landscape Report
Tree wounds and healing, Got Nature? Blog
Fall webworms: Should you manage them, Got Nature? Blog
Purdue Landscape Report Facebook Page

The Purdue Landscape Report


treeAroundHouseQuestion: Can tree roots cause damage to a home’s foundation? I have a 3’ in diameter pin oak tree that is within 10 feet of my house. A certified arborist took a look at it and said that he would like to use an Air Knife to expose the roots near the foundation (a walkout basement) to determine if the roots are causing damage and/or need to be pruned, or whether the tree needs to be removed since it is situated too close to the house. Before I spend $500 for them to use the Air Knife, I wondered if you thought it would be worthwhile or not necessary.

Answer: Tree roots can damage a house foundation, with an invitation to do so. Tree roots are very opportunistic and will only grow and penetrate where it is easiest to grow such as friable soils and mulch. Typically, when roots encounter solid, impervious surfaces such as pipes, sidewalks, curbs and foundations, they are redirected laterally or up and over. However, if there is a breach or a crack nearby, they can and will exploit those voids in search of moisture. Such as sewer pipes aren’t damaged by the roots, they are just very capable of finding those leaks and moving into the moist and often nutrient-rich pipe.

Roots normally grow horizontally and not very far beneath the soil surface. Sometimes when roots encounter the looser backfill soil near the foundation, they can abruptly start growing down. You may be able to locate these roots, if they exist, by excavating a foot or two down within a few feet of the foundation. If you find a suspect root, cut it off. Unfortunately, in some cases excavation down to the base of the foundation may be necessary. This may have to be done anyway to repair and stabilize it. Cutting the roots should prevent future problems, especially if a root barrier is installed to prevent re-growth.

Resources
Surface Root Syndrome, The Education Store, Purdue Extension resource center
The Nature of Teaching: Trees of the Midwest, The Education Store
Tree Appraisal and the Value of Trees, The Education Store
Construction and Trees: Guidelines for Protection, The Education Store

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources


Purdue Extension forester Lenny Farlee says we can thank wildlife, especially birds, for the spread of wild black cherry trees. This tree-sized cherry tree has shiny, elongated leaves with finely toothed margins, and a very dark, flaky bark to go with tiny berries.

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
Black Cherry, The Education Store, Purdue Extension resource center
Beware of Black Cherry Toxicity; It’s Weedy, Too, Indiana Yard and Garden – Purdue Consumer Horticulture
Black Cherry, Native Trees of Indiana River Walk, Purdue Fort Wayne
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist

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


In this video, Purdue Wildlife Extension Specialist Jarred Brooke will talk about some of the reasons why you might consider a late growing season burn as opposed to a dormant season prescribed fire.

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
Wildlife Habitat Hint, Playlist, Purdue Extension – Forestry and Natural Resouces
A Woodland Management Moment, Playlist
Woodland Stewardship for Landowners, Playlist
Renovating Native Warm-Season Grass Stands for Wildlife: A Land Manager’s Guide, The Education Store, Purdue Extension resource center
Prescribed fire: 6 things to consider before you ignite, Got Nature? Blog, Purdue Extension – 4Forestry and Natural Resources

Jarred Brooke, Wildlife Extension Specialist
Purdue Department of Forestry and Natural Resources


On this edition of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to American beech. You can identify this shade-tolerant species by its simple leaves with veins running parallel out to small teeth on the edge of the leaf, as well as smooth gray bark.

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
American Beech, Native Trees of Indiana River Walk, Purdue Fort Wayne
Beech, The Education Store, Purdue Extension resource center
American Beech, Purdue Arboretum Explorer
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist

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


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