What is this on my Pluot?

First year after planting bare root in Winter, Brown mottling and holes in leaves. Doesn’t seem to be insect related. I had a few aphids around but the neem spray seemed to take care of that. Noticed this after not checking in on the tree for a week or so. We’ve been having somewhat wet weather so I’m wondering if it’s related to that but doesn’t seem to look like the major plum diseases I’ve read about… Are you able to identify it?

I’d be curious as well, some of my pluot leaves have looked like that the past 2 years.

Doesn’t happen on mine in a dry climate. So it’s likely bacterial or fungal related to wet weather.

Maybe shot hole fungus?

Yes that looks like shot-hole to me… Many of the pluots are highly susceptible to it. Shot-hole is usually bacterial spot in the east and in the west I think it may more often be coryneum blight - ? The treatment is similar.

Thank you, I hadn’t been able to find much detail on pluot specifically, so was looking at plum. Some of the photos i’d seen on plum for shot hole had much larger, less crowded looks to them but it was the one that seemed most likely.

When you say similar treatment, you mean dormant sprays? What about now after leaf out? Also is neem an effective fungicide?

Shot-hole can look very different depending on weather conditions. It is treated with early spring sprays, starting with delayed dormant. Also a fall copper spray at leaf fall is helpful. Neem is not effective for shot-hole. You can spray copper up to shuck split, or chlorothalonil. After shuck split just wait til the fall to spray.

My pluots are having almost the exact same appearance now (it rained several times the past couple of weeks), severity varies from variety to another… Flavor Supreme is the worst followed by FK. Splash and ED are the least affected. I did spray dormant copper, chlorothalonyl a couple of weeks ago and serenade last week ( and with the chlorothalonyl). It doesn’t seem that this spraying helped much… Last year I sprayed copper in early May, but that was too much for the pluots and they suffered phytotoxicity and dropped 99% of the crop.

It could be shot hole but check after dark with a flashlight for earwigs. Some of my untreated cherries and plums are infested by midnight. They look like small cockroaches and may cause significant damage to young growth.

I caught some in the act this morning. Here is the video:

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Scope creep a bit here, but given this tree in my original post and another tree, a Weeping Santa Rosa plum, exhibit pretty much the same symptoms, I wanted to provide an update and get further ideas.

I don’t doubt this is called “shothole” but I am a little confused as it seems that can be caused by multiple fungal or bacterial pests. Any reliable way to control an unknown type or am I bound to have to send in samples somewhere to get this pinpointed? Or there is some kind of generalized control to fix this…?

Both trees have been sprayed with fixed copper in the last dormant season.

There is a combination of the following symptoms:

  • Darkened spots, or dead/dried spots, or holes where the dead/dried spots have fallen out (this is the most noticeable symptom and quite clearly present on all leaves that have grown earlier in the season while the fresher growth doesn’t have it/hasn’t allowed the affliction to yet propagate to it)
  • Deeply curled, “scrunched” leaves (you can see this in the broader shot of a section of the tree)
  • Some but more limited general bronzing, red coloring that you might expect if we were later in the season (weather has been 70-90F for a while now, and we haven’t had any late Fall-like cool weather which for us comes usually pretty late anyway in the San Fran Bay Area)