Hole in my avocado tree's stem

Sun Mar 18, 2012 9:34 pm

Hi,

I'm hoping this looks familiar to someone. Last Thursday I noticed it looked like something burrowed into the stem of my young avocado tree. There was a hole with a lot of white powder around it. We had a lot of rain yesterday and when I went to look at my tree today the white powder wasn't around the hole anymore but a bit farther down the stem. It looks like there's a lot of powder inside the hole though.

Did some kind of bug do this? Should I be really worried it's going to keep burrowing in the tree and kill my avocado? I bought the tree last summer from Home Depot and have been trying really hard to keep it alive with our poor draining soil and the sun burn it had last year. Now it's finally growing again after being stagnant for 6 months...

Sun Mar 18, 2012 10:10 pm

I think this is what caused the hole in my tree:

http://www.ipm.ucdavis.edu/PMG/r8300411.html

I don't know what to do about it...

Mon Mar 19, 2012 3:17 am

The site you linked to offers management information. Unfortunately, in a tree the size of yours, it would probably mean removing and destroying the tree. If it were a side branch, you could probably get away with just removing that, but it appears to be in the main trunk.

The site also recommends certain cleanup operations necessary around the area where the tree is/was growing. It clearly states that pesticides don't work.

It does sound like your diagnosis is correct, however.

Mon Mar 19, 2012 3:24 am

I can't tell how far down the trunk this is, but I suppose one possible course of action is to try pruning it below the damage and see if the "burrow" extends downward.

...but that seems extreme without knowing for sure.

Mon Mar 19, 2012 3:28 am

Yes, I read the site and I agree the management of the worm would mean killing my tree. If only that stupid worm hadn't chosen the trunk to burrow in to

.

I'm going to keep taking care of the tree in hopes that it can outgrow the damage that worm is going to do. I'm so bummed right now.

Mon Mar 19, 2012 4:03 am

The way I interpreted it, the critter could till be in the tree.
So if I really thought it was the culprit, I would lop the trunk below the damage and dispose of the upper portion and any affected portion of the trunk below the damage (burning would be ideal but not feasible for me so by some other thorough method).

Young avocados tend to be pretty forgiving of severe pruning, so I would hope the tree would grow new shoots and branches, especially now heading into growing season.

Mon Mar 19, 2012 4:29 am

applestar wrote:I can't tell how far down the trunk this is, but I suppose one possible course of action is to try pruning it below the damage and see if the "burrow" extends downward.

...but that seems extreme without knowing for sure.

That certainly sounds like a better option than destroying the whole tree. I'm going to watch the burrow entrance closely to see if it gets bigger. I tried to go after the worm today but the tree's bark had already healed over the entrance and I didn't want to open it up again. The tree looks so much healthier lately I can't believe this borer larvae had to go and ruin things!