Trees are valuable additions to the home landscape. When problems arise with the health of a tree, it can be difficult to determine what is causing the issue.
Many factors can cause trees to become unhealthy and lose their aesthetic value or die. Some of those factors include:
- environmental stresses
- site problems
- animal injury
- infectious diseases
- insect infestations
Frequently more than one factor is involved. A correct diagnosis of the problem(s) is the important first step in trying to manage an unhealthy tree.
Look to Abiotic Issues First
Often, insects or diseases are the first things we look to when pinpointing why a tree is unhealthy. However, in many cases, environmental stress and issues with the site (abiotic issues) are the primary cause of the problem, even when insects or disease-causing agents (biotic issues) are present. Those biotic issues are more likely to become an issue because abiotic issues weaken the tree.
Identifying Tree Problems
Use these resources to help evaluate the site, growing conditions, and the tree itself. This is the first step to identifying the cause of the decline.
Identifying Tree Problems
a comprehensive resource that outlines the steps used for examining unhealthy trees.
Understanding Decline in Trees
a resource that provides tips on identifying, preventing, and reducing the factors that lead to tree decline.
It outlines several potential causes of decline in trees, particularly those problems related to the planting site and environmental conditions.
Help for Newly Planted Trees
Trees planted within the last three to five years are more likely to see problems than established trees.
Learn about the many factors that could contribute to the decline or death of a newly planted tree in this article: Decline of Newly Planted Trees
Resources for Common Tree Problems
Environmental Stresses
- Causes of Branch Dieback on Trees
- All About Stem Girdling Roots
- Winter Damage to Trees – including sunscald, desiccation, and rodent damage
- Frost and Freeze Damage
- Peeling and Splitting Bark
- Understanding the Effects of Flooding on Trees (PDF)
- Managing Storm-Damaged Trees (PDF)
- Construction Damage to Trees
- Grade Change Damage to Trees
- How to Manage Trees Near Sidewalks
- Nutrient Deficiencies in Trees
Insect Problems on Trees
- Scale Insects on Ornamental Landscape Plants (PDF)
- Insect Galls on Trees and Shrubs (PDF)
- Bagworm
- Carpenter Ants
- Emerald Ash Borer
Disease Problems on Trees
- Anthracnose of Shade Trees (PDF)
- Verticillium Wilt of Woody Plants (PDF)
- Fungal Cankers of Trees (PDF)
- Oak Wilt - Identification and Management (PDF)
- Dutch Elm Disease
- Oak Tatters
Common Issues with Conifers
- Common Diseases of Conifers in Iowa (PDF)
- Pine Wilt (PDF)
- Browning of Conifer Needles
- Seasonal Needle Drop
- Rhizosphaera needle cast
- Stigmina Needle Cast
- Cytospora canker
Finding a Certified Arborist
Sometimes it is worth hiring a certified arborist to come on site and evaluate your tree.
You can search for a certified arborist in your area using a city name or zip code on the Trees are Good website.
Use this publication to evaluate and select the best arborist for you: Choosing an Arborist (PDF).