Shelf or bracket fungi appearing on any tree is a sign of heartwood rot....it is dying from the inside out. Some trees can survive wih this for many years but it is just a matter of time.

argh... I feel so regretful at cutting it too heavily... it's such an old tree and so big...

Is the trunk healthy? (Probably not, given the fungal infection, but worth asking). You could try stumping it. This is a technique developed at UC research station for commercial growers to enable them to grow avocados productively (fruit!) with less water.

Search on "stumping an avocado tree" for more information.

And as to your pruning the tree too hard, the stumping technique is used commercially so what you did was likely not the issue. Avocado trees only live so long, and we had that terrible drought...

Thanks so much hoovb! I am going to try it this weekend and post some photos. I am going to take out that thick branch with the mushrooms and paint it and see if that'll help. Or should I just remove the mushrooms off the branch and paint it for now instead of cutting to see if fungi grows again? The main trunk doesnt seem to have the infection yet. But it's close to those 2 infected branches.

Heartwood rot is just that....a fungal rot of the interior portion - the 'heart' - of the tree. So it is very likely that the trunk portion is infected as well even though it may not be showing any exterior fungal development. There is nothing that can be done about this - no treatment - so removing the fungi you see, pruning, painting or anything else is not going to help.

Agreeing with all above, however before you take out the tree just cut off the infested branches first and see what happens. Remember to cut down to just above where the branch originates from the trunk. Leave about a one inch collar to allow for healing. If when you do this you notice hollowness or large amounts of discoloration, then you should take the tree out. PS, I noticed some kind of cable or rope that is stretched around the branches, what is that?

Cheers, Frank

I made the mistake of cutting off too many large branches few years ago.

==>>> even in tree time.. which is counted in decades ... i wonder if your original cutting had much of anything to do with this .... trees just dont rot that fast.. especially in dry regions ...

what you dont tell us.. is what prompted you to cut in the first place??? .. perhaps because it was already structurally unsound???

i too wonder about the wires.. and in the 3rd pic.. why it seems to be growing horizontally ... rather than vertically ... did it already fall over ???.... or is the pic turned???

if you have more space in the yard.. you might want to plant a new tree ... so regardless of what happens with this one.. you have a new one on the way ... in tree time ...

trees dont live forever ... especially when forced into submission in a backyard .. and yours appears old and huge [for what i know about them ...lo.] .... do what you can ... but dont blame yourself.. nor worry about it ...

ken

ps: any idea how to get elton out of my head ....

I had the ropes there to keep the new shoots from falling. A lot of the new shoots were drooping down so I just wanted to attach them to the older bigger branches in case they fall down. I originally did massive pruning 2 years ago because it was dropping a lot of leaves every day into my yard and also a lot into my neighbors yard so just wanted to make it more manageable. Didnt know any better. Foolish...

Here's photo of some cuts I made just today on some of the smaller branches off the infected branch. Do they show starting rot at the center?

I'm going to hire someone to do the older infected branches later this week and take those down.

The smaller branches won't necessarily show rot because they are originating from the healthy, living, outside part of the main trunks. The problem will be that the larger infected branches with the rot will no longer be strong enough to support the expanding crown and will continue to decline, possibly spreading further into the tree.

A rejuvenating pruning as suggested above, will remove any weak, diseased portions of the trunks so the new branches that originate from what remains will have sufficient support in the future. :^)

Yeah the guy's going to come next week to cut the main branches and I'll share photos of what those trunks look like once cut.... I am really hoping tree can be saved. It's really old. Maybe 30+ years old. It was here before we moved in.

Well, it might take a couple/few years but from what I've read, these trees are tough. You have a very well established root system with a tree like that so it might take a little structure pruning along the way to develop good form. Usually when a tree comes back from the stump, the growth tends to be on the wild side with long shoots and huge leaves, but I'm not an Avocado tree guy so can't really say for sure. Usually with structure pruning is you just keep an eye on the growth each year and do a little clip here and there so the tree assumes nice form. What that is for Avocados idk. Good Luck! :o)

Here's photos of the cut major branches. I cut basically all the major branches leaving almost no leaves. Keeping fingers crossed.

Some more photos. Tomorrow, I am thinking about painting the cut wounds with white rubber patch for roofing and sealing it. And maybe spraying some fungicide on it first.

From look of photos what do you guys think? Will it survive?

No, don't seal the wounds!

That used to be a recommended procedure but has been debunked for quite a while now.

Covering tree wounds link:

No as Bill_minn said, don't paint it with anything.

Make sure the area around the tree has a fluffy mulch to protect the roots from too much heat. The root system will now be exposed to the full heat of California sun this summer, so protect the area with mulch. (Keep the area immediately adjacent to the trunk--several inches--clear of mulch).

Remember for future reference Avocado trees drop a lot of leaves. It's what they do. Most of them right as, and right after, they flower in spring. Then they grow almost a whole new set of leaves.

Can we see a picture of the stump?

I just noticed there's still a tiny area in center that's rotting. Should I cut more? I didnt see it yesterday because it was covered with some shavings. Or should I take a drill bit and drill out that dark area at the center?

And this is the other major branch... There's some discolored area on the side. Should I cut that part out?

Looks like possible polyphagous shot hole borer damage as well as the white-rot fungi (the beatles could be spreading it as they enter the tree). I would use a contact insecticide like Talstar on the trunk, larger branches, and on the cuts you made removing damaged limbs from the tree. If you do decide to spray use protective gear as specified on the label and be very careful not to get any drift on flowers (to protect bees). If you don't want to spray, then keep a lookout for additional symptoms and remove affected branches down to the branch collar as they appear.

Thanks, I'll try and spray some termite insecticide on it this weekend.