Triple Crown Blackerry Galls
About four years ago, I put in a long row of cane berries including: triple crown, tayberry, marionberry, raspberry, and munger raspberry in our backyard garden. In the triple crowns, I have been noticing canes splitting for the last two seasons or so. It has been progressively getting worse. I'm worried it is cane gall, caused by an Agrobacterium.
Today, I can find small splits in the raspberry canes as well. If it is cane gall, what are my options? Does it affect other types of plants as well or just cane fruits?
I'm so sad. Thank you for your help!
Washington County Oregon
Thank you for your question. Since your photos did not match up with any raspberry issues pictured in our pathology literature, I asked Professor Jay Pescheid what his opinion is, and he says: "Well, we certainly have crown and cane gall in the PNW:
The first image is reminiscent of this problem but it is kind of limited and the other images do not show it. My first instinct would be to cut into the center of the canes and see if there is an insect associated with the damage. Or verify that there is un-organized plant cells that are typical of crown gall. Beyond that I do not have good ideas other than sending in a sample. But by that time they may have removed it all and that is what we would recommend in the first place."
If you would want to submit your plant samples to the pathology clinic, you can use the contact and other information on this web page: https://bpp.oregonstate.edu/plant-clinic/submit-sample/how-submit-plant-materials
Professor Pescheid put your photo on the Plant Pathology Facebook page, and got another suggestion: "Depending on where this blackberry is-also check for tunneling , frass and larvae as rose stem girdler can cause galls on stems. Prevalent in the south Puget Sound area on raspberry and blackberry." Hope this is helpful!
These berry canes are in Hillsboro, OR. I'll do the suggested checks and post more photos.
It is insect damage!
I broke open many of the galls on the triple crown canes to find tunnels, frass, and even a live larve.
The raspberry canes had similar damage, but to a far lesser extent. They appear to travel in spirals under the skin, then settle in and do some damage and move on.
Great research! Here is an article about this pest: https://pnwhandbooks.org/insect/small-fruit/cane-fruit/cane-fruit-rose-stem-girdler
Great, thank you!
Most welcome! Mystery of the month!