Several of my kaki (North GA, zone 8a) are suddenly dying, after being the picture of health and vigor for the last several weeks.
Apparently healthy leaves are just dropping off, still green, followed by the bare new stems shriveling up. A bark scratch test reveals green cambium. All trees were purchased from mail-order nurseries and are presumably on northern D.V. rootstock. There are a few other kaki (another Fuyu and a Giombo) that are so far not afflicted.
The first to be struck down by the mystery affliction is a Saijo. Following is a timeline.
Suffice it to say, this is extremely discouraging. Are the symptoms consistent with kaki SDS? Is there anything else that could be a plausible explanation? Finally, can anyone recommend a course of action? Are these trees doomed, and are they likely to infect my remaining kaki persimmons if I don’t remove them?
Were these plants you grafted yourself or did you purchase them somewhere?
If purchased, when did you purchase them? How long have they been in the ground?
If you grafted them yourself, when did you graft and from where did you source your scion wood? (if from a private party, say that. If from multiple sources, share that)
They look like great plants (except for the dying and leaf issues). How far away are the other kaki?
I’m sure others will chime in (my own kaki experience is limited to IKKJ and a couple American/hybrid varieties).
The Saijo depicted above was purchased from Just Fruits & Exotics in Feb 2022 and was put in the ground that winter.
The Nikita’s Gift was purchased from PlantMeGreen (Simpson Nurseries) also in February 2022, and planted that winter.
The Fuyu was purchased from Ison’s in 2020 and planted that winter.
I have a number of other kaki persimmons (another Saijo, a few Giombos, another couple non-astringents, a Coffee Cake, a Chocolate, and a Tanenashi) and none of them appear to be affected. However, the time interval between perfect health and severe decline appears to be a matter of days, if not hours.
What exactly is the black poly around each tree? I can imagine any feeder roots that come in close contact might be cooked with the sun exposure to that dark color. What would happen if you just simply remove that and replace it with a couple inches of mulch so that feeder roots could see a more friendly environment? Also I would think your trees cannot properly respirate with the plastic in place. Tree roots need access to oxygen to adequately utilize the sugars produced by the foliage. That’s just what I see that might make a difference, maybe others have more ideas
Dennis
Kent, Wa
I was thinking the same, maybe fungus on the roots, but also voles. This has happened to me with other young trees. One year we lost six trees within 2 weeks. One day the tree was fine and by the evening it was a wilted standing corpse.
It is a compressed, non-woven geotextile fabric that is UV stable. It is permeable to gas and water – you can pour a cup of water right through it – but it is thick enough to mostly block weeds from growing up (it will not block roots, so the surface must be kept reasonably clear of debris to keep weed seeds from landing on it and germinating).
I considered the problem of heat retention and have tested the soil temperature with a thermometer. In the daytime, the soil surface is several degrees cooler under the fabric than it is on bare turf. Just in case, though, I have a thin layer of light mulch (shredded wood chips, less than an inch) as an insulator.
I got the idea from one of @Alan’s posts from long ago (I don’t know if he uses or endorses this method).
It seems to work well for me – I have over 100 trees using the fabric as a barrier and growth has been excellent, even in Las Vegas where the sunlight is quite a bit more intense than in Georgia.
I considered that, but although I have a few moles (the grub-eaters) in the yard, thankfully I have never had voles and I don’t see any evidence of them (other than my dying kakis, I guess).
If the problem were root damage of any sort, I would have expected to have seen the leaves exhibit signs of dehydration / nutrient starvation. That is not the case here – the leaves are green and firm, and are just dropping off, with the only apparent pathology (to me) being those small black streaks along the veins. Meanwhile, the cambium under the bark of the trunk is green.
In the linked thread, there is a discussion of graft incompatibility. If there were just one problem tree, I’d see that as a possible issue. But to have Saijo, Nikita’s Gift and Fuyu all decline more or less simultaneously after 2-4 years suggests that the cause is something in the immediate environment.
What happened in the immediate environment on April 12-20? Did you fertilize? Spray insecticide? Introduce a new tree that may have harbored an insect pest or disease? What else?
Yes, this is what is particularly concerning and is making me think it’s pathogenic.
No sprays (ever) on these trees, and the last fertilization event was more than a month ago, before bud break. The trees got a light amount of 10-10-10. I was actually just about to fertilize them again this week, but I haven’t gotten around to it – I’m glad, too, because then I’d be inclined to pin it on the fertilizer.
As for the immediate environment, this has been the best growing year here in at least five years. Mild winter, last frost before bud break, and Garden of Eden weather, with mild temps, light rains (0.25 inches) every few days, and otherwise sunny. The soil is moist but definitely not water-logged.
The nearby trees (mostly Asian and European pears and jujubes) are doing great.
Notably, the last tree I added was a potted Cardinal persimmon from One Green World, planted this winter. It was a tiny little grafted twig, and did not wake up from dormancy. It was maybe 200 feet from the Saijo and 30 feet from the Nikita’s Gift.
Here is a young Giombo (planted in 2022, also from PlantMeGreen) that is neighbors to the stricken Saijo – it looks perfectly healthy:
Well, Mrs. Lincoln, other than that, how was the play?
In this area (the back yard), in addition to the afflicted trees, there is a 5th leaf, productive Fuyu, a 3rd leaf Saijo that looks fine, and a Giombo planted in 2022.
There are other kaki on the other side of the house, along with some American persimmons, and they all look fine. For now.
Sorry to see that. I have had a few cases, last year a tree started to fade but somehow it pulled out of it. Those drooping shoots with no leaves is what my tree looked like. The black veins in the leaves is a common symptom of kaki in trouble. The trouble leading to these symptoms could be one of many things. For my recent tree I have no idea. I have had grafts get unhappy and show a lot of that black in the leaves so graft issues can be one thing. My recent tree only had the problem on half of the tree so it was not the graft.
Does one of your State universities offer plant diagnostic testing? I’ve used ours on occasion and it’s pretty helpful.
Usually they can test for diseases and evidence of pesticide damage.
I can say from personal experience being surrounded by corn and soybean fields, that spray drift can be unpredictable. I’ve seen trees hit with other trees nearby untouched.
From what I’ve read it’s a big problem in the cotton belt too. Any chance you’re near cotton fields? Here in Iowa corn and soybean fields are getting sprayed now.
That is a good idea. I don’t know if UGA deals a lot with kaki, though.
This area is no longer agricultural, and there are no nearby cotton fields. Plus, if it were spray drift, it would have had to pass over pears, mulberries, jujubes, muscadines, and berry bushes to reach my kaki – and it would be odd that some of the kaki would be spared.
I had grafted an DV variety to a DV rootstock and we had the worst drought last summer. Suddenly these blue veins started showing up in the underside of the leaves. My tree ended up being fine and is coming back vigorously this spring.
Now I know my tree is a DV and not an Asian variety, but is the bluing that takes place on the veins of the leaf just a symptom of stress or is it the actual disease that kills many Asians with SDS? And if it is the disease, are Americans just able to survive due to increased vigor?
Ps. I’m not trying to derail to conversation, I’m just genuinely curious about the phenomenon of blue veins and SDS.
To the extent my opinion matters as the OP, I don’t think you’re derailing the thread at all. I’m trying to come up with any hypothesis that fits the evidence, hoping that there might be some treatment or hope for recovery — and wondering if my other persimmons, almost all of which are on D.V., are at risk. Any discussion of persimmon diseases that pattern-match in a significant way to my symptoms is welcome.
We just had a good rain start up last night — about an inch worth so far, and it is still going. I’m curious to see if that will have any effect.
As another act of desperation, I ordered this Cal-Mag Extreme micronutrient supplement and plan to apply it as soon as it arrives. I last had a soil test years ago and at that time, my soil was slightly acidic with no deficiencies, but these trees are basically coding right now so I figure I have little to lose.
Found by means of perplexity.ai :
" Cephalosporium diospyri causes persimmon wilt, a fungus disease that kills many trees in central Tennessee and the Southeastern States (1). The disease is characterized by a sudden wilting of the leaves, followed by defoliation and death of the branches from the top down. An infected tree often lives 1 or 2 years after this symptom appears. Diseased trees should be burned, and cuts and bruises on other trees should be painted to prevent entry by wind-borne spores. No disease-resistant trees have been found. A wound is necessary for primary infection. The hickory twig girdler and powderpost beetle cause the majority of wounds in healthy trees. As soon as the tree dies, the fungus produces spores in large quantities between the bark and the wood near the base of the tree." (souce: Diospyros virginiana L "
I don’t think kaki get that disease, only virginiana. Xylella fastidiosa is now one of the bigger suspects. There is a very good chance that a virus is involved in many cases.
This is where I get confused. I’ve read that SDS is mainly affecting Asians in the southeast and not the Americans. Also in another thread it listed the pathogen as believed to be Xylella fastidiosa. Your post mentions a different pathogen causing persimmon wilting and mentions DV specifically.
So is SDS and Persimmon wilt different things altogether?