Compiled by Brian Hudelson and Hulubanche Kassa
The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from June 20, 2026 through June 26, 2026.
Broad-Leafed Woody Ornamentals
Plant: Boxwood
Disease/Disorder: Fusarium Canker
Pathogen: Fusarium sp.
Counties: Dane, Fond du Lac, Outagamie, Waukesha
Plant: Boxwood
Disease/Disorder: Volutella Canker
Pathogen: Volutella sp.
Counties: Dane, Fond du Lac, Outagamie, Waukesha
Plant: Elm (‘Princeton’)
Disease/Disorder: Sphaeropsis Canker
Pathogen: Sphaeropsis sp.
County: Dane
Plant: Elm (Unspecified)
Disease/Disorder: Dutch Elm Disease
Pathogen: Ophiostoma sp.
County: Waukesha
Plant: Honeysuckle
Disease/Disorder: Powdery Mildew
Pathogen: Oidium sp.
County: Dane
Plant: Hornbeam
Disease/Disorder: Herbicide Damage
Pathogen: None
County: Walworth
Plant: Hydrangea (Oak Leaf)
Disease/Disorder: Fusarium Canker
Pathogen: Fusarium sp.
County: Walworth
Plant: Hydrangea (Oak Leaf)
Disease/Disorder: Phomopsis Canker
Pathogen: Phomopsis sp.
County: Walworth
Plant: Lilac (Shrub)
Disease/Disorder: Anthracnose
Pathogen: Colletotrichum gloeosporioides
County: Pierce
Plant: Lilac (Shrub)
Disease/Disorder: Bacterial Blight
Pathogen: Pseudomonas syringae pv. syringae
County: Pierce
Plant: Magnolia
Disease/Disorder: Herbicide Damage
Pathogen: None
County: Walworth
Plant: Maple (Unspecified)
Disease/Disorder: Anthracnose
Pathogen: Discula sp.
County: Dane
Plant: Oak (Unspecified)
Disease/Disorder: Herbicide Damage
Pathogen: None
County: Walworth
Plant: Redbud
Disease/Disorder: Herbicide Damage
Pathogen: None
Counties: Green, Walworth
Field Crops
Plant: Soybean
Disease/Disorder: Seed Rot/Seedling Blight
Pathogen: Phytophthora sp., Fusarium oxysporum
County: Winnebago
Forage Crops
No New Diseases
Fruit Crops
Plant: Apple
Disease/Disorder: Root/Crown Rot
Pathogen: Rhizoctonia sp., Fusarium sp.
County: Outagamie
Plant: Cherry
Disease/Disorder: Brown Rot
Pathogen: Monilinia sp.
County: Grant
Plant: Cherry
Disease/Disorder: Physiological Fruit Cracking
Pathogen: None
County: Grant
Plant: Strawberry
Disease/Disorder: Fusarium Wilt
Pathogen: Fusarium oxysporum
County: Dane
Plant: Strawberry
Disease/Disorder: Root/Crown Rot
Pathogen: Phytophthora sp.
County: Dane
Herbaceous Ornamentals
No New Diseases
Houseplants
No New Diseases
Needled Woody Ornamentals
Plant: Hemlock (Eastern)
Disease/Disorder: Hemlock-Poplar Rust (Suspected)
Pathogen: Melampsora abietis-canadensis
County: La Crosse
Plant: Pine (White)
Disease/Disorder: Dothistroma Needle Blight
Pathogen: Dothistroma sp.
County: Dane
Vegetable Crops
Plant: Fluted Pumpkin
Disease/Disorder: Cucumber Mosaic
Pathogen: Cucumber mosaic virus
County: Dane
Plant: Fluted Pumpkin
Disease/Disorder: Impatiens Necrotic Spot
Pathogen: Impatiens necrotic spot virus
County: Dane
Plant: Onion
Disease/Disorder: Chemical Burn (Suspected)
Pathogen: None
County: Washington
Plant: Potato
Disease/Disorder: Bacterial Soft Rot
Pathogen: Pectobacterium atrosepticum
County: Portage
Plant: Spinach
Disease/Disorder: Chemical Burn (Suspected)
Pathogen: None
County: Washington
Plant: Tomato
Disease/Disorder: Herbicide Damage
Pathogen: None
County: Dane
Specialty Crops
No New Diseases
Miscellaneous
No New Entries