Rust fungal infections can be exceedingly common on Serviceberry and other rose-family hosts (crabapple, hawthorn, etc.). This looks like Cedar-Quince rust instead of Cedar-Apple, but that isn't terribly important with regards to actions to take. The spores it is producing now are carried on the wind to juniper hosts, so will not be re-infecting the Serviceberry. They can be trimmed off at any time, and the swollen twig tips they created will die back to that point anyway. Since little damage is done, aside from aesthetic impacts, the tree should be fine and no intervention is needed.

There are no fungicides that will treat or cure its infection at this point, as they are only effective as a preventative when applied before infection sets in each spring. Even so, treatment would need to cover about 8-10 weeks of a vulnerability window during which time the spores on infected junipers are moving on the wind to Serviceberry, and this risks exposing the plant's blooms to a fungicide spray that might potentially harm pollinators. Since this disease is more cosmetic than serious, and for sustainability reasons, we discourage the use of fungicide for suppressing rust. Fortunately, weather conditions play a large role in disease spread and severity from year to year, so outbreaks won't always be as drastic every year.

Miri

Thank you so much for the speedy and helpful response to my question. I’ll prune off the areas and dispose of them in the trash. I’m glad to hear that this is not a certain death sentence for my sweet little tree!!

You're welcome!

I posted your response on the Howard County Gardeners Facebook group as well. When I asked the question in that group I got no responses or feedback…so hopefully sharing your reply will help to educate/assist anyone who may have a similar issue. 

Thank you for the heads-up. If useful, we recently filmed a short video about rust on Serviceberry, which is on our YouTube channel as well as embedded on our Rust Diseases of Trees web page. (Which admittedly needs some polishing and better photos, but we're focused on more urgent page updates for the moment.)

Miri

Thanks, I’ll check it out!!