Dormant Cedar Apple Rust Gall

Subject: Egg Case?
Location: Gainesville, Georgia
March 4, 2014 9:12 am
One of my students found this on an evergreen tree in his yard. It is approx. 1 inch long. Is this an egg case or a part of the tree?
Signature: K. Baer

Cedar Apple Rust Gall

Dear K. Baer,
This is a Gall, which is a generic name for a growth on a plant.  Many are caused by insects, mites and other “bugs” but this is a Cedar Apple Rust Gall in its dormant state and it is a fungus.  Here is what the Missouri Botanical Garden website states:  “Symptoms on juniper: Brown, perennial galls form on twigs. When mature (usually in two years), the galls swell and repeatedly produce orange, gelatinous telial horns during rainy spring weather. The galls of cedar-apple rust are often over 2 inches in diameter, while cedar-hawthorn rust galls are rarely over 2 inches in diameter. Occasionally the twig beyond the gall dies, but usually no significant damage occurs on the juniper host.”
  The University of Missouri Extension website has more images and information.

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