Got Nature? Blog

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.

Full Article >>>

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: Understanding Damage, Risk and Recovery – Got Nature? Blog, Purdue Extension – FNR
Why Is My Tree Dying? – Got Nature? Blog, Purdue Extension – Forestry and Natural Resources
Tree Risk Management – Got Nature? Blog, Purdue Extension – FNR
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

---

As trees grow and reach heights which many consider to be unsafe, tree owners would often top their trees by reducing the tree size. This is by heading back most of the large, live branches from the tree. However, topping trees proves to be more damaging than beneficial.

Topping trees can cause decay, weak branch attachments, and an increased likelihood of failure. If we do not top our trees and leave them to develop naturally, the structural strength of the trees is stronger than those that are not topped. The extensive root system, when left undisturbed, provides adequate support for the trees.

This publication titled What’s Wrong with Topping goes in-depth on the implications of topping and provides better alternatives to topping.

To view other urban forestry publications and video resources, check out Purdue Extension’s The Education Store website.

Resources:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension YouTube Channel
Tree Selection for the “Un-natural” Environment, The Education Store, Purdue Extension resource center
Tree Installation: Process and Practices, The Education Store
Tree Pruning Essentials Video, Purdue Extension YouTube Channel

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

---

Spring is here! It is the time of year for some of us to be planting new trees. In this Ask an Expert session, we welcome Lindsey Purcell, urban forestry specialist, as he teaches us how to plant and properly care for our trees. He goes over the tree selection process, including which invasive species trees we should avoid, and how to continue to take care of our trees once planted.

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:
Planting Your Tree Part 1: Choosing Your Tree, Purdue Extension YouTube Channel
Tree Planting Part 2: Planting a Tree, Purdue Extension – Forestry and Natural Resources YouTube Channel
Indiana Invasive Plant List, Indiana Invasive Species Council, Purdue Entomology
Alternatives to Burning Bush for Fall Color, Purdue Landscape Report
Invasive Plant Species: Callery Pear, Youtube, Purdue Extension
Equipment Damage to Trees, Purdue FNR Extension
Landscape Report Shares Importance of Soil Testing, Purdue FNR Extension

Lindsey Purcell, Urban Forestry Specialist
Purdue Department of Forestry 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

---

Curious about the upcoming cicada emergence? What is different about this species than the ones you see every summer? What effect can they have on wildlife or on your trees and shrubs? Find out from Purdue Extension wildlife specialist Jarred Brooke, forester Lenny Farlee and Purdue Entomology’s Elizabeth Barnes. Don’t miss the question and answer time with our experts discussing “all things cicadas”.

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:
17-year Cicadas Are Coming: Are You Ready?, Purdue Landscape Report
17 Ways to Make the Most of the 17-year Cicada Emergence, Purdue College of Agriculture
Periodical Cicada in Indiana, The Education Store, Purdue Extension resource center
Cicada Killers, The Education Store
Purdue Cicada Tracker, Purdue Extension-Master Gardener Program

Dr. Elizabeth Barnes, Exotic Forest Pest Educator
Purdue Department of Entomology

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

Jarred Brooke, Wildlife Extension Specialist
Purdue Forestry and Natural Resources

---

Purdue Landscape Report: PART 1 – The Importance of “Physical” Soil Testing
In my 40 years of teaching and consulting, one of the biggest and most frustrating problems I continually encounter is when so called “landscape professionals” and homeowners continue to apply annual soil fertilizers, lime, and other soil amendments without ever conducting a professional soils test.

Before planting long-lived trees, shrubs, flowering perennials and lawns, it is absolutely essential to have your soil tested for its physical, chemical, and biological properties. To have a beautiful landscape, an awesome lawn, or a very productive vegetable garden, we need to do soil tests because the health and vigor of everything we grow is directly dependent on the soil we are growing our plant’s roots in.

As an analogy, when you go to a family doctor or physician, why will they usually require a professional blood test from you?  They want to “show you the numbers” of your cholesterol, HDL, LDL, triglycerides, sodium, potassium, and a whole array of other very important blood tests. Again, if they prescribe you to take medications, but they are not helping and can actually hinder your health, lawsuits can definitely occur. I tell my students, before anything is applied on a client’s property, “show me the numbers”!

Although many intelligent homeowners and landscapers may have initially done a chemical soil test, many have never done a soil texture, soil compaction, and/or soil drainage test on their property or their clients. Why do we need to do these “physical” soil tests?  Think about it. For root growth, its not just about nutrient deficiencies, toxicities, or soil acidity problems, its about life giving oxygen in the root zone. Without oxygen, the entire ecosystem below ground will suffer. This is why I recommend you to determine your soil texture, (sand, silt, and clay %’s). Professional soils labs can determine your soil’s texture and that is very important, not only for knowing how much and when to water, but to determine what kind of fertilizers will work best for your soil. Many sandy soils are nutrient deficient because they have little negatively charged organic matter or clay to hold onto the positively charged nutrient fertilizers (cations). Excess rain and watering will leach many of the quick-release fertilizers, especially nitrate and potassium out of the root zone. This is why I recommend slow-release fertilizers on most soils so your plant’s roots will have available nutrients for a much longer time.

For full article >>>

Resources
Soil Sampling Guidelines, The Education Store, Purdue Extension resource center
Soil Testing for Lawns, The Education Store
Consumer Horticulture: Collecting Soil Samples for Testing, The Education Store
Certified Soil Testing Laboratories, Purdue Extension – Master Gardener Program
Example soil test form

---

In this edition of ID That Tree, Purdue Extension forester Lenny Farlee introduces you to the white oak group. In addition to identifying four common varieties of white oak by their leaves and acorns, he also explains how to differentiate them from their cousins, the red oaks.

 

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
White Oak, The Education Store, Purdue Extension – Forestry and Natural Resources
FNR Hardwood – White Oak, The Purdue Arboretum Explorer
White Oak, Native Trees of Indiana River Walk, Purdue – Fort Wayne
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources 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 Resources

---

In this edition of ID That Tree, we introduce you to the cucumber magnolia. This native Indiana species is much like other members of the magnolia family, except it has green cucumber like fruit and a unique bark. Learn more from Purdue Extension forester Lenny Farlee.

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
Indiana’s Native Magnolias, The Education Store, Purdue Extension resource center
Cucumber Magnolia, Native Trees of Indiana River Walk, Purdue Fort Wayne
Magnolia Acuminata, The Purdue Arboretum Explorer
ID That Tree, Purdue Extension – Forestry & Natural Resources 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

---

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 Bare Root 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
Investing in Indiana Woodlands, The Education Store
Tree Appraisal and the Value of Trees, The Education Store
Forest Improvement Handbook, The Education Store

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

---

Calling all teachers and parents: Do you need some new ideas on how to get students out in nature or teach them science lessons?

We’ve got you covered with our Nature of Teaching program. We’ve created more than 40 sneak peek videos that introduce you to our lesson plans, offering a quick way for teachers and other K-12 leaders to view the lessons as well as the related activities.

Many of the lesson plans meet state specifications for Next Generation Science Standards and/or Core Standards, while also offering informal curriculum items and fun activities for all K-12 leaders.

The Nature of Teaching program offers three areas of formal and informal activity-based curricula centered around getting youth outside: wildlife, health and wellness, and food waste.

Sneak Peeks videos include topics ranging from producers, consumers and natural resources and food waste from farm to fork, to exploring nature with your senses and emotional vocabulary exploration, to trees of the Midwest and healthy water/happy home.

Subscribe to the Nature of Teaching YouTube Channel for more Wildlife, Food Waste, and Health and Wellness information.

Resources
Nature of Teaching Website
Nature of Teaching YouTube Channel
Nature of Teaching Program Receives Environmental Education Award, College of Agriculture, Purdue University
Resourceful Animal Relationships, The Education Store, Purdue Extension resource center
The Nature of Teaching: Food Waste Solutions, The Education Store
Benefits of Connecting with Nature, The Education Store

Rod N Williams, Professor of Wildlife Science
Purdue University Department of Forestry and Natural Resources

---