At the Plant and Insect Diagnostic Clinic, we often receive questions from tree enthusiasts: Is my tree sick?
To pinpoint the problem, observe the tree, the symptoms, and review how the tree is being cared for, especially if the tree is young. To learn more about the types of symptoms to look for in our pictorial Glossary.
Ask the following questions:
Is a young tree receiving good care? This includes routine watering during dry spells and mulch to help retain soil moisture; this gives the trees a better chance of establishing and thriving. See the Tree and shrub care page for tips and resources.
Is there a root flare? Any injuries in the trunk and at the tree's base?. Lawn mowers, insects, and many other factors can cause damage to trees.
Are side branches wilting, looking water-deprived, leaves yellowing, or looking scorched? Progressive branch wilting is a common symptom of vascular pathogens that can be deadly to trees.
Proper diagnosis is crucial as some of these fungal pathogens can remain in the soil or mulch made of diseased trees (Verticillium Wilt). Undiagnosed infected trees may become a source of the pathogen for other healthy trees nearby as these fungi are moved by their insect vector (Oak Wilt and Dutch Elm Disease).
The tree in the photos is a suspect of Dutch elm disease. The Plant and Insect Diagnostic Clinic can test for vascular samples with a fresh and representative sample. See our detailed instructions to collect a sample on the Vascular wilts testing page.
Concerned about oaks? Do a thorough inspection and take photos; we recommend this free US forest service guide on How to recognize common diseases in oaks. Avoid pruning oaks unnecessarily because pruning can attract beetles that carry the oak wilt fungus.
We can help and assess trees through digital photos and let you know if a sample for testing is recommended. See our tips on taking and sharing photos on our page Digital Photography (Plant problems only).
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