Tree Diseases
Diagnosing tree diseases is more difficult than determining the cause of damage by other pests (ex., Ips beetles). It is necessary to understand how the trees grow and know the signs and symptoms of tree diseases. Also you need to remember that similar signs and symptoms can be caused by biotic and abiotic (nonliving) disorders.
Symptoms are the external and internal reactions to disease. Leaf spots, blight, mosaic, stunting, distortion, canker are symptoms that will help
in diagnosing tree diseases.
Biotic tree diseases are caused by fungi, bacteria, viruses, nematodes, and other living nematodes. Abiotic factors that cause tree problems are:
- Moisture imbalance
Temperature extremes
Nutrient imbalance
Pesticide/chemical injury
Improper planting and pruning
Mechanical damage
Root girdling
Poor soil drainage
Soil compaction
Natural aging of plants
It is important to diagnose tree disease before starting any control. Here are few observations you can make:
•What parts of the plant are injured?
•Has the damage spread?
•When did the damage occur?
•What signs and symptoms are visible?
•Where are signs and symptoms located on the plant?
•How severe are the signs and how often do they occur?
•Are there signs and symptoms on other plants?
When observing a diseased tree, it is always good idea to compare it to a normal tree. All trees should be examined.
Disease distribution is an especially useful diagnostic tool:
Symptom distribution on Woody ornamentals
Distribution Possible Causes
One sided Root Damage from digging or disease, wind desiccation, herbicide drift, vascular wilt
From top to bottom Mechanical damage to trunk
From bottom to top Transplant shock
From inside to outside Normal needle drop, oxygen starvation to roots, desiccation, transplant shock
From outside to inside Blight, root damage, transplant shock, herbicide damage
These are some of the clues you can use in diagnosing tree diseases.
If you find any signs of tree diseases around your property, call or contact SprayTech today to see if we can treat your trees.