Knowledgebase
Azalea Malus infested #749952
Asked May 14, 2021, 2:40 PM EDT
Multnomah County Oregon
Expert Response
Thank you for your question, Bonita. The strange upward growths on the branch appear to be witches broom, whose cause is unknown. Rhododendron-Witches' Broom | Pacific Northwest Pest Management Handbooks (pnwhandbooks.org) While there may be a disease acting on your plant, a diagnosis cannot be made without your submitting plant tissue and, perhaps, a soil sample to the OSU Plant Clinic (| College of Agricultural Sciences | Oregon State University).
The photo with the larva on it shows lichens growing. The lichens are not harmful to the plant, but often grow on plants that are in distress and failing from other causes. I am unable to identify the species of insect with just this photo. Although you can send it to the OSU Insect Identification lab (OSU Insect ID Clinic (oregonstate.edu)), I would suggest that your azalea may have out-lived its (healthy) life span. It looks as though it has not had regular pruning, and it may be in soil that is not acidic enough to allow it to uptake nutrients.
I am sorry I cannot be more helpful. Good luck!
Thank you for your quick response to my Azalea issue. I’ll follow through with pruning the overgrown old branches away and try to amend the soil to make it sustain this venerable old plant. The new growth sprouting at the base has healthy wood without moss though many of their leaves are also eaten back to the stems. Some branches here and there have normal leaves thankfully. Appreciate your advice.
Bonita
From: Ask Extension <<personal data hidden>>
Sent: Friday, May 14, 2021 1:49 PM
To: Bonita Sells <<personal data hidden>>
Subject: Re: Azalea Malus infested (#0019883)
If you are intending to keep it, I suggest you get a soil test to ensure that it has the correct (acidic) soil pH and enough nutrients. Analytical Laboratories Serving Oregon | OSU Extension Catalog | Oregon State University Another one of your plant's problems may be its inability to uptake nutrients. Good luck!