How to Identify Common Tree Diseases

NWI Tree Service • August 7, 2024
how to identify common tree diseases image

Trees are an integral part of our environment, providing beauty, shade, and a habitat for wildlife. However, like all living things, trees can fall victim to various diseases. Identifying these diseases early can save your trees and prevent the spread to others. Here’s a guide to help you recognize some of the most common tree diseases in Minnesota and Wisconsin. 


Let’s Talk About Stress


Just like us, trees can get stressed, and stress increases their susceptibility to diseases. Environmental factors such as drought, poor soil conditions, and physical damage can weaken trees, making them more vulnerable to infections. Guess the doctor was right, huh? Managing stress is
crucial for both humans and trees! Go figure! 


Identifying Common Tree Diseases

  • Symptoms: Wilting, yellowing, and premature leaf drop, typically starting from the upper branches.
  • Causes: Fungal infection spread by bark beetles.
  • Treatment: Pruning infected branches, fungicide injections, and removing severely affected trees.

Image Source: https://extension.umn.edu/plant-diseases/dutch-elm-disease

  • Symptoms: Wilting leaves, leaf discoloration, and sudden leaf drop, usually starting at the tree top.
  • Causes: Fungal infection spread through root grafts and beetles.
  • Treatment: Trenching to prevent root graft spread, applying fungicides, and removing infected trees.

  • Symptoms: Dark, sunken lesions on leaves, stems, flowers, and fruits; defoliation (losing its leaves).
  • Causes: Fungal infection favored by wet conditions
  • Treatment: Proper sanitation, pruning affected areas, and fungicide applications.

Image Source: https://extension.umn.edu/plant-diseases/anthracnose-trees-and-shrubs 

  • Symptoms: Bright orange spots on leaves and fruit of apple and crabapple trees; swollen galls on cedar trees.
  • Causes: Fungal infection requiring both cedar and apple/crabapple trees to complete its life cycle.
  • Treatment: Removing nearby cedar trees, applying fungicides, and selecting resistant varieties. 

Image Source: https://www.fs.usda.gov/wildflowers/plant-of-the-week/gymnosporangium_juniperi-virginianae.shtml

  • Symptoms: Blackened, wilted leaves and branches, often appearing scorched; cankers on branches.
  • Causes: Bacterial infection favored by warm, humid conditions. 
  • Treatment: Pruning infected areas, applying bactericides, and practicing good sanitation.

Image Source: https://extension.umn.edu/plant-diseases/fire-blight

Diagnosing Tree Diseases by Species


The Minnesota and Wisconsin Departments of Natural Resources provide resources to help identify diseases based on the specific type of tree or plant. This is particularly helpful for pinpointing the exact issue your tree may be facing. 


Visit the Minnesota DNR to identify tree diseases

Visit the Wisconsin DNR to identify tree diseases


Focused Tree Care


We understand that tree care can differ between regions. At NWI Tree Care, we have tailored our services to address the specific needs and condition of trees in Minnesota and Western Wisconsin. Our local expertise ensures that your trees receive the best care possible, customized to the local environment. 


Expert Tree Disease Management Services in Minnesota and Wisconsin


By understanding the common tree diseases and their symptoms, you can take proactive steps to protect your trees. If you suspect your tree may be infected, don’t hesitate to reach out to the professionals at NWI Tree Care. We’re here to help you keep your trees healthy and your landscape beautiful. 


Why Choose NWI Tree Care?


At NWI Tree Care, we understand the importance of maintaining healthy trees and the challenges posed by tree diseases. Our team of experts is equipped with the latest techniques and equipment to diagnose and treat a wide range of tree diseases. Here’s why you should choose us:

  • Experience and Expertise: Our specialists have extensive knowledge and experience in tree care.
  • Friendly Service: We pride ourselves on providing exceptional customer service with a friendly approach. 
  • Fair Pricing: We offer honest and competitive pricing for all our services. 
  • Professionalism and Integrity: We are committed to delivering high-quality workmanship with integrity. 


Don’t wait until it’s too late!
Contact NWI Tree Care for a free, no-obligation consultation to address any tree diseases or concerns you may have. Let us help you keep your trees healthy and thriving! 

Two green leaves are sitting next to each other on a white background.

Call Us Today to Schedule Your Consultation


651-504-8387

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