Raspberry problem. - Ask Extension
Some of the clusters of flowers on my raspberry vines are having an issue. The stem near the cluster seems to be eaten or just weakened is a specific ...
Knowledgebase
Raspberry problem. #793496
Asked May 31, 2022, 2:38 PM EDT
Some of the clusters of flowers on my raspberry vines are having an issue. The stem near the cluster seems to be eaten or just weakened is a specific way. Some of them are broken clear through while others just seem to have the top part of the stem gone. see photos.
Thanks.
Multnomah County Oregon
Expert Response
The floral canes seem to have a physical cut or bite on the side of the inflorescence. There is missing tissue and what is left has a russetted appearance. That is a typical wound response. I suspect a caterpillar of some type bit the side of these flowers and it now does not have the ability to stand on its own so it flops over and dies. The real question is what type of insect has made the damage. I am not the expert you need to answer that question.
Hello,
It appears that the damage could be caused by an insect larvae that has cut the stems and the weight of the leaves/fruits and caused it to tip over.
One potential cause is the rose stem girdler, but the damage is showing up earlier than expected for that insect: https://pnwhandbooks.org/insect/small-fruit/blackberry-raspberry/blackberry-raspberry-rose-stem-girdler
There could be other potential pest and you'd need more evidence to determine the cause.
Through the course of the season, watch for insect pest activity and compare with the descriptions here:
https://pnwhandbooks.org/insect/small-fruit/blackberry-raspberry
Unfortunately, without more clues, I can't diagnose the problem at this time.
It appears that the damage could be caused by an insect larvae that has cut the stems and the weight of the leaves/fruits and caused it to tip over.
One potential cause is the rose stem girdler, but the damage is showing up earlier than expected for that insect: https://pnwhandbooks.org/insect/small-fruit/blackberry-raspberry/blackberry-raspberry-rose-stem-girdler
There could be other potential pest and you'd need more evidence to determine the cause.
Through the course of the season, watch for insect pest activity and compare with the descriptions here:
https://pnwhandbooks.org/insect/small-fruit/blackberry-raspberry
Unfortunately, without more clues, I can't diagnose the problem at this time.
