When to spray for brown rot shoot blight on Nanking cherry

Hi everyone. I have a couple Nanking cherry bushes that are almost 7 years old and have gotten quite large. The last couple years they have flowered profusely, but then not made any fruit whatsoever and also lots of the twigs and branches go brown and die. The flowers dry up and die too without making fruit - though maybe they are drying up and falling off like an unpollinated flower would. Described in this thread:

So current theory is that the bushes are being hampered by brown rot shoot blight (Monilinia laxa). The question is: this year can I spray something to help with this? If so, what should I spray and when? I have never sprayed anything on these bushes before.

Right now I’m thinking I’ll spray some oil and copper late dormant to start, since I’ll be spraying oil on apples and pears anyway. I was fortunate to get in on the recent Indar group buy, so I will have a small bottle of that at my disposal. So I was thinking maybe spray that just before, during, or just after blooms. I got some Immunox last year for my grapes but my understanding is that it is nearly useless for brown rot.

I would be grateful to hear your thoughts.

Found this paper from Europe which seems to say copper + seaweed extract is effective:
https://www.researchgate.net/publication/256486299_Control_of_brown_rot_blossom_blight_Monilinia_laxa_on_apricot_in_organic_agriculture/link/0c9605230c28990fff000000/download

Another paper which says lime-sulfur is useful:
https://apsjournals.apsnet.org/doi/pdf/10.1094/PD-89-1164

Michigan state says to spray “one at popcorn and one at bloom”. The products it lists are all commercial stuff but Indar is in there. They recommend rotating between Indar and something else so resistance is not developed.

One of the others recommended there is available in semi-resonable $ amounts (Topsin M)

Another useful chart with a number of things listed with relative efficiency:
http://ipm.ucanr.edu/PDF/PMG/fungicideefficacytiming.pdf

It does sound like shoot blight. I have gotten it on some of my middle eastern apricots. Indar will work very well. You can alternate with sulphur or lime sulphur. I currently alternate with Elevate or propiconazole.

In terms of timing it is warmth plus wet that brings it on so right after rains is a good time. Sulphur you put on before the rain and lime sulphur after.

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My Carmine Jewel bush Cherry gets that or a related fungus.I used Spectracide’s Immunox,which has Myclobutanil and it helped quite a bit.Being a systemic though,has me wanting something else.
So,Captan will be tried this year and resistance can’t be built up,like Immunox.
Captan can be sprayed pre-bloom,bloom and after also.
Also,last season,for the first time,it looked like my Apricots and Plums has some of that going on.

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My sister planted a Nanking cherry 44 years ago at my parents home and it’s had maybe a dozen cherries in that time. Early blooming and frost kills or lack of pollination, or both most likely. (But, hey, it’s still alive…and not more than 6 feet tall.)

I got shoot blight on tart cherries. Not sure if bacterial or fungal. It wiped out my North Star after a few years. Then I got it at another location on Surecrop cherry. I heard spraying copper at white bud stage would help. I did that and no blight that year! Did it again the following spring and no issues again.