Disease Hotline Issue 19

Microscopic close-up of Cercospora leaf spot on Endless Summer big leaf hyrdrangea (Hydrangea macrophylla 'Bailmer'); note, purple halo around spot.

Photo by Missouri Botanical Garden, Kemper Center for Home Gardening, IPM

Cercospora leaf spot on lower leaf surface of Endless Summer big leaf hyrdrangea (Hydrangea macrophylla 'Bailmer').

Photo from the Missouri Botanical Garden, Kemper Center for Home Gardening, IPM

Cercospora leaf spot on upper leaf surface of Endless Summer big leaf hyrdrangea (Hydrangea macrophylla 'Bailmer').

Photo from Missouri Botanical Gardens, Kemper Center for Home Gardening, IPM

Cercospora on Rose

Photo by Jody Fetzer, New York Botanical Garden, Bugwood.org

Black Spot on Rose

Photo from the Iowa State University Plant Disease Clinic

Black Spot on Rose

Photo from the Iowa State University Plant Disease Clinic

Mutinus caninus, a type of stinkhorn, growing on mulch

Photo by Paula Flynn, Extension Plant Pathologist, Iowa State University