Skip to content

Cedar Apple Rust

Look what the rains brought out! These orange alien fruiting bodies belong to Gymnosporangium juniperi-virginiana, the fungus that causes cedar apple rust. I finally found one so that I can share a picture that I took! We have had a lot of rain in the past week, and I saw this one along my route to work. This rust has two hosts, the juniper on which these gall are formed and rosaceous hosts primarily apple. The fantastic spore tendrils come out in the spring in response to rains. The teliospores on these structures produce basidiospores which go to the newly expanding leaves of apple and crabapple. Fungicdes can help to protect the apple. Pruning out the galls on juniper will help to break the cycle of spores. Gall will last several years on juniper and get larger each year. This one was at least three inches across, when sporulating!
NFG 5/13/2018

Print Friendly, PDF & Email
Published on Categories Hot TopicsTags , , , , ,

About cmanneri

Christy is a graduate of the Biden School of Public Policy and Administration at the University of Delaware with a master's in Public Administration. She is the chief operating officer of a local non-profit, 3B Brae’s Brown Bags and a Communications Specialist for the University of Delaware. Her research interests include issues of social justice, such as nutritional insecurity, community re-entry, and domestic violence. She also volunteers with her local school district and has a deep passion for education policy, as she believes many social injustices stem from inequitable opportunities in education.