Service Berry Tree Disease - Ask Extension
(Amelanchier) are commonly affected by fungal rust diseases from the genus Gymnosporangium, most notably cedar-quince rust, cedar-apple rust, and ceda...
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Service Berry Tree Disease #942459
Asked August 14, 2026, 7:13 PM EDT
(Amelanchier) are commonly affected by fungal rust diseases from the genus Gymnosporangium, most notably cedar-quince rust, cedar-apple rust, and cedar-hawthorn rust. These fungi require an alternate host—typically nearby junipers or eastern red cedars—to complete their multi-year life cycle.
I found this information that seems to fit for what I found on my service berry tree this June when I harvested the berries. I want to know how to treat the tree to protect it. I am delayed in sending this to you and hope it's not too late to do something.
Blue Earth County Minnesota
Expert Response
The advice about not planting junipers, cedar, etc. near your serviceberry is too late. If the fruit was ruined by the rust, it is inedible. However what you can do is find the galls on the juniper, cedar or whatever serves as the alternate host and cut them off. I found galls years ago on one of my hardy native roses. I cut the galls off and continued to monitor for new ones. There is no product you can use on your serviceberry to prevent the rust. Removing the galls is the only way to prevent infection other than removing the alternate host. Sorry.
