This tree was growing back nicely and it just rained again a lot temps went from upper 70’s to 45°f now today I notice die back on the top of the tree and black near the branch ends. Even on the lower branches.
Could this be from the new cedar mulch I placed on last week? I don’t see dieback on the other tree a 6’ away.
I’m assuming it’s from rain, virus or wet feet and will open up the mulch to dry out sooner. So my question would be if it going to keep spreading? Any recommendations? It’s planted about 2’ high in a 70/30 sandy loamy top soil/compost which seems to be fairly good drainage.
If you prune off just below the dead parts, do you see gray/brown streaks in the wood? I would lean toward Verticillium as the causal agent, but it could be something else. There’s a photo at the top of this page that shows what the xylem streaks look like:
I’ve also had one tree that was infected with Verticillium from a scion purchased on Etsy, and the tree seems to have recovered, but I no longer collect scionwood from it because I assume it is still infected. There’s no cure, but most trees do outgrow it if they aren’t small seedlings.
That’s not how I’ve seen sunburn present itself, but it could be I guess. I think most CA growers don’t bother with painting avocado branches and rarely see sunburn, which is more of an issue in the hot SE or really hot places like Arizona. I know that Brad Spaugh has been known to rant about how it’s completely unnecessary to paint avocados.
To me it looks fungal. When you cut long thin cuts, do you see those streaks like in my earlier link? Basically cut a long thin slice with a knife as if you’re going to use those pieces you removed for a whip graft.
I pulled a couple piece out and one I scraped the skin. It was shallow and clean underneath. This one in the first pic I cut a little deeper and didn’t see anything bad. The bottom pic is the top I took off that looks ok too. I cut that a few inches under the black part.
Ok, I agree, not seeing the streaks! Still does seem like an odd pattern of dieback for sunburn though. Usually that seems to only damage parts of leaves and one side of the stems, not kill whole sections like that suddenly.
Yes agreed. Especially starting with the dieback of the fresh new leaves. That was the first think I noticed the other day.then today I saw that black on the stem and the leaves were fried. Well fingers crossed this don’t keep spreading. The good thing is no rain and it’s supposed to reach the 80’s finally. Wonder if I should use a wound sealer on the cuts I just made?
Yeah definitely something else caused it to defoliate, but it’s super susceptible to sun scald until it puts on a canopy again. Was it under drought stress? I cured mine with more water, it was under too much stress not having enough water causing it to be weak to sun and this wilt.
I had it in a 15g next to the house and covered throughout the winter. I definitely deprived of water but then when I uncovered it rained a lot so the poor tree has gone through it. I’m heading over to Sherman Williams now to grab a gallon of ultra white satin latex now. I think it will work better than the Go Natural paint since it’s white. Appreciate you guys!
