Deciduous Tree Leaf Disease Quick Reference

Authors: Brian Hudelson, UW-Madison Plant Pathology
Last Revised: 04/09/2009
X-number: XHT1190

Anthracnose Hosts: Most trees, commonly ash, maple and oak Pathogens: Gloeosporium spp. as well as other fungi Signs/Symptoms: Blotchy dead areas on leaves For more information see: UW Garden Facts XHT1001a/b/c

 

Purple-Bordered Leaf Spot Host: Amur, Japanese, red, silver and sugar maple Pathogen: Phyllosticta minimaSigns/Symptoms: Discrete, circular leaf spots with purple borders For more information see: UW Garden Facts XHT1149

 

Tubakia (Actinopelte) Leaf Spot Hosts: Oak Pathogen: Tubakia spp. (Actinopelte spp.) Signs/Symptoms: Discrete circular, or irregular blotchy dead areas on leaves For more information see: UW Garden Facts XHT1104
Scab Hosts: Apple, crabapple, pear, mountain-ash Pathogen: Venturia inaequalis Signs/Symptoms: Circular, black leaf spots with feathery edges; eventual leaf loss For more information see: UW Garden Facts XHT1007a/b
 Cedar-Apple Rust Cedar-Apple Rust Hosts: Apple, crabapple, hawthorn Pathogens: Gymnosporangium spp. Signs/Symptoms: Bright yellow-orange, circular leaf spots For more information see: UW Garden Facts XHT1009a/b
Powdery Mildew Hosts: Most deciduous trees Pathogens: Several genera of powdery mildew fungi Signs/Symptoms: Uniform/blotchy powdery white areas on upper and lower leaf surfaces For more information see:UW Garden Facts XHT1005
Downy Leaf Spot Hosts: Hickory, walnut Pathogen: Microstroma juglandis Signs/Symptoms: Discrete powdery white areas on lower leaf surfaces
Chlorosis Hosts: Oak, red maple Cause: Iron or manganese deficiency, often induced by high soil pH Signs/Symptoms: Yellow leaves with dark green veins For more information see: UW Garden Facts XHT1002
Scorch Hosts: Most deciduous trees Cause: Water stress induced by drought, high soil salt content, or other water-limiting factors Signs/Symptoms: Dead tissue on leaf margins
Tatters Hosts: Most deciduous trees, but commonly oak Cause: Possible early season cold injury Signs/Symptoms:Lacy, tattered-looking leaves For more information see: UW Garden Facts XHT1141

 

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