Compiled by Brian Hudelson and Hulubanche Kassa

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from May 30, 2026 through June 5, 2026.

 

 

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Broad-Leafed Woody Ornamentals

Plant:  Aspen (Quaking)
Disease/Disorder:  Venturia Leaf Spot/Blight
Pathogen:  Venturia morelettii
County:  Green Lake

Plant:  Boxwood
Disease/Disorder:  Fusarium Canker
Pathogen:  Fusarium sp.
County:  Milwaukee

Plant:  Boxwood
Disease/Disorder:  Volutella Canker
Pathogen:  Volutella sp.
Counties:  Calumet, Milwaukee

Plant:  Buckthorn (Common)
Disease/Disorder:  Fusarium Canker
Pathogen:  Fusarium sp.
County:  Rock

Plant:  Buckthorn (Common)
Disease/Disorder:  Shoot Blight
Pathogen:  Asteromella sp. (Suspected)
County:  Rock

Plant:  Buckthorn (Common)
Disease/Disorder:  Tubercularia Canker
Pathogen:  Tubercularia sp.
County:  Rock

Plant:  Hibiscus
Disease/Disorder:  Herbicide Damage
Pathogen:  None
County:  Boone (IL)

Plant:  Hickory (Shagbark)
Disease/Disorder:  Diplodia Canker
Pathogen:  Diplodia sp.
County:  Dane

Plant:  Holly
Disease/Disorder:  Cytospora Canker
Pathogen:  Cytospora sp.
County:  Milwaukee

Plant:  Holly
Disease/Disorder:  Diplodia Canker
Pathogen:  Diplodia sp.
County:  Milwaukee

Plant:  Hydrangea
Disease/Disorder:  Herbicide Damage
Pathogen:  None
County:  Boone (IL)

Plant:  Maple (Korean)
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  Dane

Plant:  Maple (Red)
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Sphaeropsis sp.
County:  Dane

Plant:  Maple (Sugar)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Waukesha

Plant:  Maple (Unspecified)
Disease/Disorder:  Anthracnose (Suspected)
Pathogen:  Discula sp.
County:  Waukesha

Plant:  Ninebark
Disease/Disorder:  Powdery Mildew
Pathogen:  Oidium sp.
County:  Waukesha

Plant:  Tree (Unspecified)
Disease/Disorder:  Anthracnose
Pathogens:  Gloeosporium sp.
County:  Dane

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Field Crops

No New Diseases

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Forage Crops

No New Diseases

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Fruit Crops

Plant:  Blueberry
Disease/Disorder:  Winter Injury (Suspected)
Pathogen:  None
County:  Jefferson

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Herbaceous Ornamentals

Plant:  Monarda
Disease/Disorder:  Crown Gall
Pathogen:  Agrobacterium tumefaciens
County:  Ottawa (MI)

Plant:  Prairie Smoke
Disease/Disorder:  Damping-Off
Pathogens:  Pythium sp., Rhizoctonia sp.
County:  Rock

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Houseplants

No New Diseases

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Needled Woody Ornamentals

Plant:  Arborvitae
Disease/Disorder:  Winter Burn (Suspected)
Pathogen:  None
Counties:  Dane, Walworth

Plant:  Juniper
Disease/Disorder:  Cedar-Quince Rust
Pathogen:  Gymnosporangium clavipes
County:  Waukesha

Plant:  Juniper
Disease/Disorder:  Cytospora Canker
Pathogen:  Cytospora sp.
County:  Waukesha

Plant:  Juniper
Disease/Disorder:  Kabatiella Tip Blight
Pathogen:  Kabatiella sp.
Counties:  Dane, Waukesha

Plant:  Pine (Limber)
Disease/Disorder:  Root/Crown Rot
Pathogen:  Phytophthora sp.
County:  Dane

Plant:  Pine (Unspecified)
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  La Crosse

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Vegetable Crops

Plant:  Potato
Disease/Disorder:  Leaf Blight
Pathogen:  Phytophthora nicotianae
County:  Unknown (MO)

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

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Specialty Crops

No New Diseases

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Miscellaneous

No New Entries

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