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sharon2079

Roses dying back quickly

7 years ago

I thought it was from scale.... but now I am pretty sure it is from raspberry cane borers because while I was out lamenating over the death of a couple of huge canes trying to figure out what could be killing the rose I saw a raspberry cane bore.... or something closely related to him... in fact I almost didn't believe what I was seeing because I did NOT even know we had raspberry cane borers.... we can't grow raspberries here.... but I saw enough of these growing up to recognize what it was of know it is a family that looks close to him... I also google the picture of it and YEP it looked just like it.... but I can't find out what KILLS them... they recommend cutting back....

well I certainly can't cut off all the canes.... and some of the canes are are infected down low... not on tops but maybe two to three inches off the graft union... in fact I am wondering if they got into the graft union.... I lost a rose bush very close to one of the worst infected roses early this spring... I just thought it was cancer and I kept cutting the canes and then there was NOTHING to cut back and the graft union was hollowed out....


What insecticide kills raspberry borers... These definitely are not bees or sawflies....

Thanks


Comments (10)

  • 7 years ago

    Have Nots Found it yet. Unfortunately. :-(

    sharon2079 thanked Vaporvac Z6-OhioRiverValley
  • 7 years ago

    I lose canes to what Kim I think called flat head apple borers. I have only seen the cane damage and had to prune the canes off. I could do without them happily too.

    sharon2079 thanked Sheila z8a Rogue Valley OR
  • 7 years ago

    No, I don't know either . I never knew they exist here in FL .
    jin

    sharon2079 thanked Plumeria Girl (Florida ,9b)
  • 7 years ago

    So tell how this works... When I cut back I was told never to take more than a 1/3 of the bush back.... it looks like the borers entered maybe 1 2 and 3 feet off the ground. One bush has every cane bored into (found that out this morning when I went to cut out the other bad limb.... these things are vociferous). Do I, can I, should I cut this bush back to the bud union - especially in the hot humid summer. I know people up north cut back and have winter die back to the ground... but I never thought about that. I have just tried to strictly stay to the 1/3 rule.

    These roses are on fortuniania.

    Thanks for helping the paranoid scaredy cat who is afraid of killing her roses.

    Sharon

  • 7 years ago

    Do Raspberry Cane Borers also like Blackberries? We have wild blackberries all over this end of Florida. I'm forever ripping the thorny vines from my flowerbeds.

  • 7 years ago

    I’m from an area where roses routinely die back to the ground. Even here I’m not a big fan of having to cut a rose all the way back in the hottest part of the summer. That’s a lot of energy needed in an all ready stressed rose.

    In my opinion I‘d forget that cur back rule. When a cane has been compromised wether it’s from an insect, disease or weather it will not be healthy. That’s one reason we cut back to healthy pith.


    I have many different types of borers. The ones I have now start at the top the cane. They do not enter thru a cut end thou I do have that type as well. I do seal all of my cut ends. The borers that are out there right now enter the soft new growth. When they enter down lower I don’t always find them until pruning.


    If your insect is the raspberry cane bore you will see this; https://www.canr.msu.edu/news/controlling_raspberry_cane_borer

    My thought is if the bores are are all ready down low on the cane you need to cut until you find them or they can kill the rose anyway.Good luck Then next time you prune always cut until you see healthy pith. Then be sure there are no holes In the pith not even very tiny ones.


    A side note... borers will also enter other plants such as phlox, rudbeckia and hydrangea among others.

    sharon2079 thanked Patty W. zone 5a Illinois
  • 7 years ago

    I don't know if they like blackberries.... I never grew them.... however, they might like them.... my neighbor has some... I actually wish I had them.... I love to EAT blackberries... one of MY FAVORITE fruits to eat.


  • 7 years ago

    Thanks Patty..... when I cut back I normally put the glue on it.... I see someone said to use nail polish... and will try that.... a few years ago I had the bee borers and started doing the glue to keep them from entering.... but now these new borers are drilling holes down in the bottom part of the canes.....

  • 7 years ago

    Sharon, I too think you are stuck cutting the damaged part off and hoping the rose can rebound. Those borers that enter a cane lower down can enter through a sunburned spot or damaged cane. Leaving the bad part on won't do much and could extend the damage I read.

    sharon2079 thanked Sheila z8a Rogue Valley OR