Cedar-Apple Rust

Red "Lipstick" Rust on Crabapples

As I was strolling through the crabapple fields in Wooster at Secrest Arboretum, I began to notice that something was significantly different than the last time that I had evaluated the trees.  Since I was evaluating the trees for apple scab, it suddenly struck me that I was also looking at a lot of polka-dot covered trees!  What in the world was going on?  As I looked closer at the foliage, the thing that stood out the most were the number of yellow-orange dots.

 

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Published on
Authors
Erik Draper

Rusts Arise!

Colorful displays of three types of rust fungi are appearing on junipers in Ohio. The fungi belong to the genus Gymnosporangium and they complete part of their life-cycle on members of the plant genus Juniperus and the other part of their life-cycle on members of the family Rosaceae. In biological terms, this type of life-cycle is known as "heteroecious."
Published on
Authors
Joe Boggs

Junipers Garnished with Tangerine Tentacles and Orange Goo.

Our wet weather this spring has triggered spectacular spore production by three types of rust fungi on junipers in southwest Ohio.  All three fungi belong to the genus Gymnosporangium and each must alternate between a member of the plant genus Juniperus and members of the rose family (Rosaceae) in order to complete their life cycle.  The requirement to cycle between two types of widely divergent host plants coupled with the rusty color of their spores earns these fungi the collective moniker of "heteroecious" rusts.

 

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Published on
Authors
Joe Boggs