Is My Blackberry Infested with Cane Borers?

[Ghadames]

Hello,

While pruning my thornless blackberry plant, I noticed these galls on its canes.

FYI, my plant is two years old. I live in southern Quebec. 2/3 of the plant was covered with snow almost the entire winter.

This gall is located at the bottom of the cane:


This one is located in the middle on a different cane:


I only have two strong big canes and a skinny one. Can someone explain exactly what they are, and if I should do something about them?

Extra info:

Last summer, cane borers attacked my raspberry plants. I was able to cut off the tilted tips and save the canes. The source of the problem was a small sick tree nearby that was infested with aphids and other insects. I saw borers too. After I removed the tree, no more tilted tips.

They might have laid eggs on my blackberry canes, but I did not see any tilted tips. I check my plants almost everyday during summer.

[valley]

Hi, Glad you've taken time to post and the pictures. I think it's time to cut a cane below the gall at that time you will look for tunneling to see how much of the plant is infested. Where the tunneling ends the plant should be safe. you still will need to spray or paint the cane and it's a good idea to use a drench, with an appropriate insecticide on the soil around the plant.

if there are wild berry patch in the area they should be removed also.

Let's see what what other ideas we get from other members, maybe someone has had success with a method that is less severe.

Good luck to you in the coming growing season.

Richard

[Ghadames]

Hi valley,

Thank you so much for the reply. I think I will cut the canes below the gall tomorrow. As for the tunnels, I don't know exactly what to look for, but if anything, I'll post pictures.

I thought that these insects remained above ground, and cutting off the infested canes would solve the problem. But from what I understand, there may be more of them below the ground level?

If I have to use an insecticide, which ones would you recommend? I'd like to solve this now before it's too late.

[valley]

Yes, that should take care of the problem. If you see a bore hole below the gall follow it down.

Richard

[Ghadames]

Alright, I cut below the galls. Here's what I found.

I dissected the galls and I found nothing that resembled to an insect. No body or anything, except wood and sap. I cut the canes many times, and I found no holes, even below and above the galls.

But here's what I noticed. All the buds below the galls had opened and there were leaves on them. Above the galls, only one or two buds had leaves. Some of them above the galls hadn't opened. Now, this could also be a normal delay, but I don't know.

On the ground level, as you can see on the pictures, the plant is thriving with new shoots.

So I'm not sure if this was an infestation, but I guess, better be safe than sorry?

How else can I know for sure that they aren't somewhere below the ground level in the roots? What are the signs of borer attack on new canes that are growing? What is it that I need to look for to prevent this from happening again (the galls, borers, whatever)?

[applestar]

I think that black color is a bit suspect, unless it's just dirt? It could be a fungal (or bacterial) infection.

Borer as name suggests, bores holes and leaves perfectly round hole and a tunnel typically in the center pith. Usually you would also find sawdust pushed out of the hole and perhaps on the ground beneath.

[Ghadames]

It appears much darker now, but I don't know if it's because it has been exposed to air and changed color. So I'm confused now. Is there anything I need to apply? How can I make sure everything is ok with the plant? The new canes seem to be growing just fine.