infestation azalea

Question: What are these? What should I do about them if anything?

responder: UVM Extension Master Gardener Volunteer www.uvm.edu/extension/mastergardener   Replied July 26, 2023, 5:18 PM EDT
response: Hi, Julius.  We're trying to figure out what this is!  We could use more photos and more information.  Our resident plant pathologist asks if you can can look inside the leaf clumps and describe/photograph any insects or caterpillars that you see.  More close-up photos would be useful.  Also, can you describe when you first noticed the problem, is it only on the azaleas, have you ever seen it before, etc.  Any extra information would be helpful.  In the meantime, one thought is that it might be azalea leaf miner.  Take a look at this link and see if it matches your situation:   https://entnemdept.ufl.edu/creatures/orn/shrubs/azalea_leafminer.htm  I look forward to hearing back from you.  I'm sure we'll find an answer.

responder: The Question Asker Replied July 26, 2023, 6:06 PM EDT
response: Hi Juanita,I dug into the clumps and found the caterpillar. Here are some more photos. I’ve only seen this on the azalea and only noticed it last week. We have only one azalea and it has been an easy pest-free keeper other than an annual azalea sawfly infestation in the spring that started a few years ago. The sawfly has been mitigated through diligent hand picking and destruction of the caterpillars and eggs in the spring.JuliusOn Jul 26, 2023, at 5:19 PM, Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied July 26, 2023, 10:07 PM EDT
response: …and 2 more:Best, Julius Goodman413.313.8441[Via mobile - please forgive brevity & typos.]On Jul 26, 2023, at 5:59 PM, Julius Goodman <<personal data hidden>> wrote:﻿Hi Juanita,I dug into the clumps and found the caterpillar. Here are some more photos. I’ve only seen this on the azalea and only noticed it last week. We have only one azalea and it has been an easy pest-free keeper other than an annual azalea sawfly infestation in the spring that started a few years ago. The sawfly has been mitigated through diligent hand picking and destruction of the caterpillars and eggs in the spring.<IMG_6462.JPG><IMG_6461.JPG><IMG_6460.JPG>JuliusOn Jul 26, 2023, at 5:19 PM, Ask Extension <<personal data hidden>> wrote:

responder: UVM Extension Master Gardener Volunteer www.uvm.edu/extension/mastergardener   Replied July 27, 2023, 10:31 AM EDT
response: Hi, Julius.  Thanks for the clear photos.  Our resident plant pathologists have looked at them and this is the response:   "Based on the images of the larva, this is likely what is called an oblique-banded leafroller, Choristoneura rosaceana. This insect has a wide host range, including rhododendrons and azaleas. They generally have two generations per year. It is hard to know for sure if the ones attacking this plant are the first or second generation. If this is the first generation they are likely to resurface if not removed and destroyed. In any case, the best option at this point is to hand pick them off and dispose of them in the trash. Next year it would be wise to scout the bushes and remove any rolled leaves or egg clusters."  Here are some links with more information and advice: https://hortsense.cahnrs.wsu.edu/fact-sheet/azalea-obliquebanded-leafroller/   https://pnwhandbooks.org/insect/hort/nursery/hosts-nursery/azalea-rhododendron-obliquebanded-leafroller  I hope this helps.  Good luck with the azaleas!

responder: The Question Asker Replied July 27, 2023, 11:12 AM EDT
response: Thank you very much. We’ll destroy the current infestation and hope that it is the first generation.On Jul 27, 2023, at 10:31 AM, Ask Extension <<personal data hidden>> wrote: