Knowledgebase
What are these swollen portions on thimbleberry stalks? #862902
Asked March 30, 2024, 11:22 PM EDT
Benton County Oregon
Expert Response
Hello Dr. Pscheidt,
Here’s a picture of the inside of the gall on a thimbleberry stalk. This gall appears to be part of the stem. Your expertise is very much appreciated!
Thank you for your help!
Jody Gordon
From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask Extension
Sent: Monday, April 1, 2024 5:07 PM
To: jodymarie4 <<personal data hidden>>
Subject: Re: What are these swollen portions on thimbleberry stalks? (#0132825)
Jody:
There are some Cynipid wasps that will create galls in/on the thimbleberry plant. That is what I believe you have. I can see some of the larva in the opened part of the gall. If you want, you can remove the galls but you will not be able to prevent the gall wasp from creating more galls in the future. I am not aware of any treatment that will work except for physical removal of the gall.
Let me know if you have any additional questions. Thank you for contacting us at Extension.
Rich