Young avocado tree trunk turning partially brown

[jbclem]

About 10 months ago my Fuerte avocado (still in container) trunk started turning brown.  The attached photos will show this.  For a while it didn't seem to be spreading any more, but a few months ago I noticed it had spread up to the top.  So I cut off the top two feet.

The tree in partially under the overhang of a large tree, so it get's some sun but is also shaded a bit from the late afternoon sun.

There are still some nice healthy looking young branches growing, just as in the photos, and I'm not sure what to do about this discoloration.  I don't want to plant it in the ground if there's some kind of terminal disease process going on. 

Can someone identify this problem?

John

ps...since I can't find any instructions on posting photos, I'm trying the "add image to post", but don't have any idea if it will work.  If there are no photos with this post, perhaps some kind soul will tell me how to post them.

 

[SonnyCrockett]

Hopefully, someone with more experience will chime in here.  I have recently had the same issue with a Simmonds avocado.  No one really specifically told me what the problem was, but from reading online, sounds like some sort of canker.  From what I was reading, it sounds like container avocados can get stressed from over or under watering and become susceptible to canker infections.  I just sprayed my trees with copper a few days ago, but I'm not sure if that will get rid of it.  Again, hopefully CTmiami (Carlos) or someone with more experience can let us know what to do, but I didn't want to leave you hanging.

[SonnyCrockett]

Alright, I talked to a well-known professional avocado farmer in South Florida and he said the trees are probably toast.  He said the black spots could be caused by some kind of wilting disease, over-watering, or over-fertilizing.  He said there usually isn't a way to treat it.  I could cut out the black spots on the trunk back to the green wood and hope it recovers, but even if it does, it will be a weak tree.  He recommends getting a new tree.

I'm still not sure exactly what caused my tree to develop these black spots, but I won't be able to travel to a decent nursery until next Spring, so picking up a new tree right now is out.  I'll keep trying different things on mine, but I don't have a lot of hope that it will make it. 

[jbclem]

I wouldn't say that I have black spots on the trunk...just that portions of it turned brown/black.  I sure wish I knew how to add photos here, the photos would describe the problem perfectly.

[Mark in Texas]

I sure wish I knew how to add photos here, the photos would describe the problem perfectly.

Right above your Reply window is an option "Add image to post".  After the window loads, hit the "Family Safe" choice then hit browse.  Select the file from your storage device to load and then click "Load it!". 

Is this what you have?
 


Noticed it on an Oro Negro about 6 months ago. Doesn't seem to hurt the tree which is very healthy and quite vigorous.

[SonnyCrockett]

This is what I'm dealing with.  One side of the trunk has turned black and brown.  The other side is still green.  Leaves look healthy and it's putting out new leaf buds like crazy.  The white marks surrounding the black parts were made by me with a wax marker, so I could see if it spreads any more.

[jbclem]

I swear the "add image to post" was not there before.  I tried using the "insert image" icon but that didn't work.  I'll try again now, and thanks for that. 

You'll see my avocado trunk isn't as blotchy as yours is.

These photos are from about ten months ago.  A few weeks ago the top 2 feet of the trunk (outside of these photos) had turned brown/black.  I cut it off.  The tree currently seems to be growing nice healthy branches, just as in these photos.  There is some green on the backside of the trunk, especially on the back of there these branches are growing...

[Mark in Texas]

You need to find out if it's cultural or a disease.  I'm pretty new to avocados so I'm not going to take a guess.  Your best resource would be Carlos here or perhaps Jim at PIN or call up a fruit specialist with your county ag dept.

[Jack, Nipomo]

Looks like sunburn to me.  Protect  exposed limbs with water-based white latex paint.

[jbclem]

If it's sunburn, will the color just stay like that without harming the tree...or can it cause changes in the tree that lead to deterioration?

[Jack, Nipomo]

If sunburn, depending on the extent of damage, the tissues die.  That would occur on the side facing the sun.  Latex paint provides a layer of protection should the damage not be too deeply into the tissue, and the white color reflects additional damage caused by the sun.  Best protection is a full canopy of leaves, but bare limbs and trunk that are exposed to sun do get sunburn even here in the cool CA coast.  Usually not fatal to the tree, but affected (not infected) limbs.

[SonnyCrockett]

Thanks for the tip.  Do the leaf buds push through the paint okay?  Yesterday, I went ahead and painted my trees with 50/50 white latex. 

[jbclem]

I have some white latex primer paint.  Is primer ok to paint on a tree trunk?  Diluted 50% of course.

[OCchris]

I have to agree with Jack- thats what I thought once the photos were provided. With an avocado that has sparse foliage the white paint is a must. Good luck, Chris