CAR is a probably bigger problem than Scab around here. It could be different temperature range humidity during the inoculation period? I was trying to fallow the Midwest pest management guide which suggest spraying fungicide / bactericide throughout the bloom period. I applied Captan as suggested which is apparently very toxic to bees and I knocked back a colony here. I don’t understand why they suggest spraying chemicals that are toxic to bees in full bloom? I see from your comments that you know better than to do this.
Actually, off the top of my head I’m unaware of Captan toxicity to bees- but I never spray it during bloom anyway- I leave the trees alone throughout bloom- all species. Captan is not very helpful against CAR in any case.
I don’t know if the incubation time for CAR is longer down there, but don’t assume it is just because your gurus for commercial fruit production call for a lot of sprays- Cornell calls for a lot more sprays than I need in small orchards as well- pressure is much higher in commercial orchards because of scale (size of orchard).
Unfortunately, the only way you can find out how little you can get away with is to risk infection to some degree- but myclo has pretty good knock out power for a rescue if needed. It also is locally systemic and doesn’t get washed off once it sets.
Captan toxic? I spray it on strawberries in bloom and haven’t seen a problem
Here at CAR Central, I find that infection depends on the weather. The galls will jelly up, then subside if dry weather comes, then jelly up again - multiple times.
I’m planning to switch from myclo to Indar for the bloom sprays on apples
They are pretty much the equivalent for early sprays but I believe Myclo is much cheaper, especially because it is available in smaller packaging. I use Indar in my second insecticide (post petal fall) spray so its legal to use on stone fruit. I only need it at that time for stone fruit for extremely early ripening varieties. Indar is much better against grown rot, of course.
I did find a good source that suggests captan has some toxicity to bees. Toxicity of Pesticides to Pollinators and Beneficials | UMass Center for Agriculture, Food and the Environment
Good to know that. I see they particularly mention mason bees.
Of course there are so many sprays you NEED to make during bloom - like strawberries for botrytis
Is it necessary to spray for CAR every year? I seem to remember reading that if you break the cycle of it moving from Cedar to Apple then the next year you won’t find CAR in apples. Or something along those lines.
I sprayed immunox on my Apple last year and had no CAR. I only had few apples that I lost to squirrels. This year I’m hoping for more apples so I’d rather not spray immunox if I don’t have to.
There is the risk of neighbors’ ornamentals harboring the CAR. I have some wild berry trees of some sort that number in the millions growing in a windbreak containing cedars that have been having a rust fest for years, just waiting for me to plant apples or pears 
So in my case, the CAR is ready to infect each year.
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If you are surrounded by host trees, both cedar and junipers and you have wet spring like I do, you will continue to get CAR. If you don’t want to spray chemical, planted disease resistant varieties may be the way to go.
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If you ever had CAR you have the other host, so you’ll keep getting it
And immunox helps with apple scab, as well
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