Cedar Apple Rust: Fungus from Space?

rust on cedar

Our recent rains are bringing out these alien-looking fungal growths on eastern red cedar and other junipers. These goo balls are a symptom of Cedar-Apple Rust, which is very common anywhere juniper and apple (or crabapple) coexist. It affects these trees, re-infecting and spreading over a mile radius each cycle.

apple leaf with rust

On the apple tree, the infections occur on leaves, fruit and young twigs. Spots appear and by late summer, tube-like structures develop on the undersurface of the leaf. Infected apple leaves sometimes drop prematurely, particularly during drought conditions or when the tree is under additional stress.

Eastern red cedars can typically withstand the galls produced by this fungus however weak or already-stressed trees will suffer compound stress if the infection is heavy.

So what do you do if you notice these symptoms on your trees? This means the fungus is already present and barring removal of one of the hosts, you’ll just want to keep these trees as healthy as possible. Remove and destroy fallen infected leaves, prune out infected twigs when practical, and reduce any possible compound-stressors.

In addition, struggling trees can benefit greatly from our compost tea fertilization, contact us today!