Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from July 12, 2025 through July 18, 2025.

 

 

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Broad-Leafed Woody Ornamentals

Plant:  Birch (River)
Disease/Disorder:  Mouse Ear (Suspected)
Pathogen:  None (nickel deficiency)
County:  Door

Plant:  Catalpa
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Dane

Plant:  Crabapple
Disease/Disorder:  Apple Scab
Pathogen:  Venturia inaequalis
County:  Sheboygan

Plant:  Hawthorn
Disease/Disorder:  Cedar-Hawthorn Rust
Pathogen:  Gymnosporangium globosum
County:  Dane

Plant:  Hawthorn
Disease/Disorder:  Sphaeropsis Leaf Blight
Pathogen:  Sphaeropsis sp.
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Herbicide Damage
Pathogen:  None
County:  Dane

Plant:  Oak (Red)
Disease/Disorder:  Chlorosis
Pathogen:  None
Counties:  Door, Ozaukee

Plant:  Oak (Unspecified)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Kenosha

Plant:  Redbud
Disease/Disorder:  Chemical Burn (Suspected)
Pathogen:  None
County:  Waukesha

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Field Crops

Plant:  Corn 
Disease/Disorder:  Bacterial Stalk Rot
Pathogen:  Dickeya sp. (Dickeya dadantii suspected)
County:  Lafayette

Plant:  Soybean
Disease/Disorder:  Phytophthora Root and Stem Rot
Pathogen:  Phytophthora sp.
County:  Columbia

Plant:  Soybean
Disease/Disorder:  Stem Canker
Pathogen:  Diaporthe phaseolorum
County:  Columbia

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Forage Crops

No New Diseases

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Fruit Crops

Plant:  Apple
Disease/Disorder:  Apple Scab
Pathogen:  Venturia inaequalis
County:  Waushara

Plant:  Apple
Disease/Disorder:  Cedar-Apple Rust
Pathogen:  Gymnosporangium juniperi-virginianae
County:  Waushara

Plant:  Apple
Disease/Disorder:   Frogeye Leaf Spot
Pathogen:  Botryosphaeria obtusa
County:  Waushara

Plant:  Apple
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Spheropsis sp.
County:  Green Lake

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Herbaceous Ornamentals

Plant:  Peony
Disease/Disorder:  Tobacco Rattle (Suspected)
Pathogen:  Tobacco Rattle Virus
County:  Florence

Plant:  Phlox
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Milwaukee

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Houseplants

No New Diseases

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Needled Woody Ornamentals

Plant:  Arborvitae
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  Columbia

Plant:  Arborvitae
Disease/Disorder:  Winter Burn (Suspected)
Pathogen:  None
County:  Columbia

Plant:  Pine (Unspecified)
Disease/Disorder:  Root Rot
Pathogens:  Rhizoctonia sp., Cylindrocarpon sp.
County:  Juneau

Plant:  Spruce (Norway)
Disease/Disorder:  Herbicide Damage (Suspected)
Pathogen:  None
County:  Milwaukee

Plant:  Spruce (Unspecified)
Disease/Disorder:  Diplodia Shoot Blight and Canker
Pathogen:  Diplodia sp.
County:  Portage

Plant:  Spruce (Unspecified)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogen:  Rhizosphaera kalkhoffii
County:  Portage

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Vegetable Crops

Plant:  Onion
Disease/Disorder:  Alternaria Leaf Spot/Blight
Pathogen:  Alternaria sp.
County:  Lafayette

Plant:  Pea
Disease/Disorder:  Root Rot
Pathogens:  Aphanomyces euteiches, Pythium sp., Rhizoctonia sp., Phytophthora sp.
County:  Clark

Plant:  Potato
Disease/Disorder:  Aerial Stem Blight
Pathogen:  Pectobacterium carotovorum subsp. carotovorum
County:  Waushara

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Specialty Crops

No New Diseases

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Miscellaneous

No New Entries

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