Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from October 11, 2025 through October 17, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

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

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

Plant:  Hydrangea
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp., Fusarium sp.
County:  Dane

Plant:  Oak (Black)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Dane

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

Plant:  Oak (Unspecified)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
Counties:  Dane, Milwaukee

(Back To Menu)

---

Field Crops

Plant:  Soybean
Disease/Disorder:  Sclerotinia Stem Rot
Pathogen:  Sclerotinia sclerotiorum
County:  Hennepin (MN)

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Waupaca

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

Plant:  Grape
Disease/Disorder:  Black Rot
Pathogen:  Phyllosticta ampelicida
County:  Price

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Leucanthemum
Disease/Disorder:  Crown Gall
Pathogen:  Agrobacterium tumefaciens
County:  Ottawa (MN)

Plant:  Leucanthemum
Disease/Disorder:  Leafy Gall
Pathogen:  Rhodococcus facians
County:  Ottawa (MN)

(Back To Menu)

---

Houseplants

Plant:  Stapelia
Disease/Disorder:  Bacterial Spot
Pathogen:  Xanthomonas sp.
County:  Dane

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Arborvitae
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp.
County:  Portage

Plant:  Fir (Serbian)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogens:  Rhizosphaera sp.
County:  Dane

Plant:  Spruce (Blue)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogens:  Rhizosphaera kalkhoffii
County:  Dane

(Back To Menu)

---

Vegetable Crops

Plant:  Cabbage (Napa)
Disease/Disorder:  Black Rot
Pathogen:  Xanthomonas campestris pv. campestris
County:  Waushara

Plant:  Cabbage (Unspecified)
Disease/Disorder:  Black Rot
Pathogens:  Xanthomonas campestris pv. campestris
County:  Waushara

Plant:  Potato
Disease/Disorder:  Bacterial Soft Rot
Pathogens:  Pectobacterium carotovorum subsp. carotovorum, Pectobacterium parmentieri
County:  Marquette

Plant:  Squash (Butternut)
Disease/Disorder:  Sour Rot
Pathogens:  Geotrichum candidum
County:  Dane

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from October 4, 2025 through October 10, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Dogwood (Red-Twigged)
Disease/Disorder:  Botryosphaeria Canker
Pathogen:  Botryosphaeria sp.
County:  Milwaukee

Plant:  Elm (‘Princeton’)
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp.
County:  Brown

Plant:  Honeysuckle (Shrub)
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp.
County:  Dane

Plant:  Lilac
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria sp.
County:  Marathon

Plant:  Maple (Norway)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Bur Oak Blight
Pathogen:  Tubakia iowensis
County:  Winnebago

Plant:  Oak (Pin)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Dane

Plant:  Oak (Red)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Milwaukee

Plant:  Oak (Red)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Milwaukee

Plant:  Oak (Red)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
Counties:  Milwaukee, Racine

Plant:  Oak (White)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Dane

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

(Back To Menu)

---

Field Crops

No New Diseases

(Back To Menu)

---

Forage Crops

Plant:  Barley
Disease/Disorder:  Blotch Spot
Pathogen:  Bipolaris sorokiniana
Counties:  Dodge, Sheboygan

(Back To Menu)

---

Fruit Crops

Plant:  Apple
Disease/Disorder:  Fly Speck
Pathogen:  Zygophiala jamaicensis
County:  Ozaukee

Plant:  Apple
Disease/Disorder:  Sooty Blotch
Pathogen:  Miscellaneous sooty blotch fungi
County:  Ozaukee

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Impatiens
Disease/Disorder: Root Rot
Pathogens:  Phytophthora sp., Rhizoctonia  sp.
County:  Oconto

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Arborvitae
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp.
County:  Waukesha

Plant:  Spruce (Black Hills)
Disease/Disorder:  Spruce Needle Drop
Pathogen:  Setomelanomma holmii
County:  Rock

(Back To Menu)

---

Vegetable Crops

Plant:  Potato
Disease/Disorder:  Bacterial Soft Rot
Pathogens:  Pectobacterium carotovorum subsp. carotovorum, Pectobacterium parmentieri
County:  Marquette

Plant:  Potato
Disease/Disorder:  Black Dot
Pathogen:  Colletotrichum coccodes
County:  Adams

Plant:  Potato
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Adams

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from September 27, 2025 through October 3, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Crabapple
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Sphaeropsis sp.
County:  Dane

Plant:  Lilac
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria sp.
County:  Walworth

Plant:  Oak (Bur)
Disease/Disorder:  Bur Oak Blight
Pathogen:  Tubakia iowensis
County:  Dane

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

Plant:  Oak (Unspecified)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Waukesha

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

Plant:  Oak (Unspecified)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Waukesha

Plant:  Rhododendron
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp., Rhizoctonia sp., Cylindrocarpon sp.
Counties:  Dane, Milwaukee

Plant:  Rose
Disease/Disorder:  Cercospora Leaf Spot
Pathogen:  Cercospora rosicola
County:  Walworth

(Back To Menu)

---

Field Crops

No New Diseases

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Grape
Disease/Disorder:  Black Rot
Pathogen:  Phyllosticta ampelicida
County:  Dane

Plant:  Grape
Disease/Disorder:  Sour Rot
Pathogen:  Miscellaneous yeasts
County:  Dane

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Sedum
Disease/Disorder: Anthracnose
Pathogen:  Colletotrichum sp.
County:  La Crosse

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Pine (White)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Dane

(Back To Menu)

---

Vegetable Crops

Plant:  Cauliflower
Disease/Disorder:  Alternaria Leaf Spot
Pathogen:  Alternaria brassicicola
County:  Dane

Plant:  Potato
Disease/Disorder:  Corky Ring Spot
Pathogen:  Tobacco rattle virus
County:  Pulaski (IN)

Plant:  Tomato
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria lycopersici
County:  Milwaukee

Plant:  Tomato
Disease/Disorder:  Sour Rot
Pathogen:  Geotrichum candidum
County:  Milwaukee

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from September 20, 2025 through September 26, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Birch (Paper)
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria sp.
County:  Door

Plant:  Crabapple
Disease/Disorder:  Gymnosporangium Rust
Pathogen:  Gymnosporangium sp.
County:  St. Croix

Plant:  Crabapple
Disease/Disorder:  Marssonina Blotch
Pathogen:  Marssonina coronaria
County:  St. Croix

Plant:  Lilac (Japanese Tree)
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Kenosha

Plant:  Lilac (Shrub)
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria sp.
County:  Racine

Plant:  Magnolia
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Brown

Plant:  Magnolia
Disease/Disorder:  Phoma Leaf Spot
Pathogen:  Phoma sp.
County:  Brown

Plant:  Oak (Bur)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Kenosha

Plant:  Oak (Bur)
Disease/Disorder:  Construction Injury
Pathogen:  None
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Monochaetia Leaf Spot
Pathogen:  Monochaetia sp.
County:  Kenosha

Plant:  Oak (Bur)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
Counties:  Dane, Eau Claire, Milwaukee

Plant:  Oak (Pin)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Winnebago

Plant:  Oak (Red)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
Counties:  Green Lake, Kenosha, Walworth

Plant:  Oak (Red)
Disease/Disorder: Chlorosis
Pathogen:  None
Counties:  Green Lake, Kenosha, Sheboygan

Plant:  Oak (Red)
Disease/Disorder:  Herbicide Damage
Pathogen:  None
County:  Kenosha

Plant:  Oak (Red)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
Counties:  Kenosha, Walworth

Plant:  Sweet Shrub
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp., Fusarium sp., Cylindrocarpon sp.
County:  Dane

---

Field Crops

Plant:  Corn (Field)
Disease/Disorder:  Root Rot
Pathogen:  Fusarium sp.
County:  Portage

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple (‘Honeycrisp’)
Disease/Disorder:  Honeycrisp Leaf Mottle
Pathogen:  None
County:  Pierce

Plant:  Apple (‘Honeycrisp’)
Disease/Disorder:  Marssonina Blotch
Pathogen:  Marssonina coronaria
County:  Pierce

Plant:  Apple (Unspecified)
Disease/Disorder:  Bitter Pit/Cork Spot
Pathogen:  None
County:  Bayfield

Plant:  Apple (Unspecified)
Disease/Disorder:  Flyspeck
Pathogen:  Zygophiala jamaicensis
County:  Bayfield

Plant:  Apple (Unspecified)
Disease/Disorder:  Frogeye Leaf Spot
Pathogen:  Botryosphaeria obtusa 
County:  Marathon

Plant:  Apple (Unspecified)
Disease/Disorder:  Marssonina Blotch
Pathogen:  Marssonina coronaria
County:  Marathon

Plant:  Apple (Unspecified)
Disease/Disorder:  Sooty Blotch
Pathogen:  Miscellaneous sooty blotch fungi
County:  Bayfield

Plant:  Apple (Unspecified)
Disease/Disorder:  Water Core
Pathogen:  None
County:  Bayfield

Plant:  Cherry
Disease/Disorder:  Cherry Leaf Spot
Pathogen:  Blumeriella jaapii
County:  Walworth

(Back To Menu)

---

Herbaceous Ornamentals

No New Diseases

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Fir (Fraser)
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp.
County:  Door

Plant:  Juniper
Disease/Disorder:  Improper Planting
Pathogen:  None
County:  Dane

Plant:  Juniper
Disease/Disorder:  Transplant Shock
Pathogen:  None
County:  Dane

Plant:  Juniper
Disease/Disorder:  Stagnospora Canker
Pathogen:  Stagnospora sp,
County:  Waukesha

Plant:  Pine (White)
Disease/Disorder: Chlorosis (Suspected)
Pathogen:  None
County:  Sheboygan

Plant:  Pine (White)
Disease/Disorder: Seasonal Needle Drop
Pathogen:  None
County:  Dane

Plant:  Spruce (Black Hills)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogen:  Rhizosphaera kalkhoffii
County:  Shawano

Plant:  Spruce (Black Hills)
Disease/Disorder:  Transplant Issues
Pathogen:  None
County:  Shawano

Plant:  Spruce (Black Hills)
Disease/Disorder:  Water Stress
Pathogen:  None
County:  Shawano

(Back To Menu)

---

Vegetable Crops

Plant:  Bean (Lima)
Disease/Disorder:  Bacterial Brown Spot
Pathogen:  Pseudomonas syringae pv. syringae
County:  Waushara

Plant:  Bean (Lima)
Disease/Disorder:  Common Blight
Pathogen:  Xanthomonas axonopodis pv. phaseoli
County:  Waushara

Plant:  Beet (Table)
Disease/Disorder:  Cercospora Leaf Spot
Pathogen:  Cercospora beticola
County:  Columbia

Plant:  Potato
Disease/Disorder:  White Mold
Pathogen:  Sclerotinia sclerotiorum
County:  Langlade

Plant:  Pumpkin
Disease/Disorder:  Plectosporium Blight
Pathogen:  Plectosphaerella cucumerina
County:  Dane

Plant:  Squash (Unspecified)
Disease/Disorder:  Squash Mosaic
Pathogen:  Squash mosaic virus
County:  Dane

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

Fungus ID:  Artillery Fungus (Sphaerabolus sp.)
County:  Dane

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from September 13, 2025 through September 19, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Boxwood
Disease/Disorder:  Volutella Canker
Pathogen:  Volutella sp.
County:  Waukesha

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

Plant:  Hickory (Shagbark)
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp.
County:  Dane

Plant:  Lilac (Shrub) 
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Sphaeropsis sp.
County:  Cook (IL)

Plant:  Oak (Bur)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Monochaetia Leaf Spot
Pathogen:  Monochaetia sp.
County:  Dane

Plant:  Oak (Northern Red)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Marinette

Plant:  Oak (Red)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
Counties:  Waukesha, Winnebago

Plant:  Oak (White)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

Plant:  Oak (Unspecified)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Waukesha

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

Plant:  Oak (Unspecified)
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Sphaeropsis sp.
County:  Racine

Plant:  Redbud
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Walworth

Plant:  Rose
Disease/Disorder:  Black Spot
Pathogen:  Marssonina rosae
County:  Milwaukee

Plant:  Sumac (Fragrant)
Disease/Disorder:  Root Rot
Pathogen:  Cylindrocarpon sp.
County:  Dane

Plant:  Viburnum
Disease/Disorder: Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  Kenosha

Plant:  Virginia-Creeper
Disease/Disorder:  Root Rot
Pathogens:  Pythium sp., Rhizoctonia sp.
County:  Dane

(Back To Menu)

---

Field Crops

Plant:  Corn (Field)
Disease/Disorder:  Gibberella Stalk Rot
Pathogen:  Fusarium graminearum
County:  Jefferson

Plant:  Corn (Field)
Disease/Disorder:  Northern Corn Leaf Spot
Pathogen:  Bipolaris zeicola
County:  Portage

Plant:  Soybean
Disease/Disorder:  Brown Stem Rot
Pathogen:  Phialophora gregata
Counties:  Columbia, Dodge

Plant:  Soybean
Disease/Disorder:  Soybean Cyst Nematode
Pathogen:  Heterodera glycines
County:  Columbia

Plant:  Soybean
Disease/Disorder:  Sudden Death Syndrome
Pathogen:  Fusarium virguliforme
Counties:  Lafayette, Sheboygan

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple
Disease/Disorder:  Bitter Pit/Cork Spot
Pathogen:  None
County:  St. Croix

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

Plant:  Avocado
Disease/Disorder:  Root Rot
Pathogens:  Phytophthora sp., Pythium sp., Rhizoctonia sp., Fusarium sp., Cylindrocarpon sp.
County:  Walworth

Plant:  Cranberry
Disease/Disorder:  Blotch Rot
Pathogen:  Physalospora vaccinii
County:  Monroe

Plant:  Cranberry
Disease/Disorder:  Early Rot
Pathogen:  Phyllosticta vaccinii
County:  Monroe

Plant:  Cranberry
Disease/Disorder:  Viscid Rot
Pathogen:  Phomopsis sp.
County:  Jackson

Plant:  Pear
Disease/Disorder:  Pear Scab
Pathogen:  Venturia pirina
County:  Vernon

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Phlox
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp.
County:  Jefferson

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Arborvitae
Disease/Disorder:  Improper Planting
Pathogen:  None
County:  St. Croix

Plant:  Arborvitae
Disease/Disorder:  Transplant Shock (Suspected)
Pathogen:  None
County:  St. Croix

Plant:  Arborvitae
Disease/Disorder:  Water Stress
Pathogen:  None
County:  St. Croix

Plant:  Juniper
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp.
County:  Milwaukee

Plant:  Pine (Swiss Stone)
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp.
County:  Milwaukee

Plant:  Spruce (Dwarf)
Disease/Disorder:  Winter Burn/Injury
Pathogen:  None
County:  Dane

(Back To Menu)

---

Vegetable Crops

No New Diseases

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

Plant:  Grass (Unspecified)
Disease/Disorder:  Rust
Pathogen:  Puccinia sp.
County:  Lafayette

Plant:  Grass (Unspecified)
Disease/Disorder:  Tar Spot
Pathogen:  Phyllachora sp.
County:  Lafayette

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from September 6, 2025 through September 12, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Maple (Norway)
Disease/Disorder:  Girdling Roots
Pathogen:  None
County:  Walworth

Plant:  Maple (Norway)
Disease/Disorder:  Overly Deep Planting
Pathogen:  None
County:  Walworth

(Back To Menu)

---

Field Crops

No New Diseases

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple
Disease/Disorder:  Cold Injury (Suspected)
Pathogen:  None
County:  Burnett

Plant:  Apple
Disease/Disorder:  Frost Crack
Pathogen:  None
County:  Burnett

Plant:  Apple
Disease/Disorder:  Sap Rot
Pathogen:  Schizophyllum commune
County:  Burnett

Plant:  Apple
Disease/Disorder:  Water Stress (Suspected)
Pathogen:  None
County:  Burnett

(Back To Menu)

---

Herbaceous Ornamentals

No New Diseases

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

No New Diseases

(Back To Menu)

---

Vegetable Crops

No New Diseases

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from August 30, 2025 through September 5, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Maple (Sugar)
Disease/Disorder:  Frost Crack
Pathogen:  None
County:  Milwaukee

Plant:  Maple (Sugar)
Disease/Disorder:  Girdling Roots
Pathogen:  None
County:  Milwaukee

Plant:  Maple (Sugar)
Disease/Disorder:  Overly Deep Planting
Pathogen:  None
County:  Milwaukee

Plant:  Redbud
Disease/Disorder:  Black Root Rot/Dead Man’s Fingers
Pathogen:  Xylaria polymorpha
County:  Waukesha

(Back To Menu)

---

Field Crops

No New Diseases

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

No New Diseases

(Back To Menu)

---

Herbaceous Ornamentals

No New Diseases

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

No New Diseases

(Back To Menu)

---

Vegetable Crops

No New Diseases

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from August 23, 2025 through August 29, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Buckeye (Bottlebrush)
Disease/Disorder:  Guignardia Leaf Blotch
Pathogen:  Guignardia aesculi
County:  Columbia

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

Plant:  Cherry (Black)
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp., Rhizoctonia sp.
County:  Dane

Plant:  Crabapple
Disease/Disorder:  Chlorosis
Pathogen:  None
County:  Green

Plant:  Elm (American)
Disease/Disorder:  Blackspot
Pathogen:  Asteroma ulmeum
County:  Waukesha

Plant:  Lilac
Disease/Disorder:  Cold Injury (Suspected)
Pathogen:  None
County:  Dane

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

Plant:  Maple
Disease/Disorder:  Girdling Roots (Suspected)
Pathogen:  None
County:  La Crosse

Plant:  Maple
Disease/Disorder:  Overly Deep Planting
Pathogen:  None
County:  La Crosse

Plant:  Oak (Bur)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

Plant:  Oak (Pin)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (Pin)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Dane

Plant:  Oak (Pin)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

Plant:  Oak (Red)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Cook (IL)

Plant:  Oak (White)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (White)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

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

Plant:  Pear (Callery/Ornamental)
Disease/Disorder:  Fire Blight
Pathogen:  Erwinia amylovora
Counties:  Dane, Waukesha

(Back To Menu)

---

Field Crops

Plant:  Corn (Field)
Disease/Disorder:  Southern Corn Rust
Pathogen:  Puccinia polysora
County:  Lafayette

Plant:  Corn (Field)
Disease/Disorder:  Tar Spot
Pathogen:  Phyllachora maydis
County:  Lafayette

Plant:  Soybean
Disease/Disorder:  Soybean Cyst Nematode
Pathogen:  Heterodera glycines
County:  Sheboygan

Plant:  Soybean
Disease/Disorder:  Sudden Death Syndrome
Pathogen:  Fusarium virguliforme
Counties:  Lafayette, Sheboygan

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple (‘Honeycrisp’)
Disease/Disorder:  Honeycrisp Leaf Mottle
Pathogen:  None
County:  Wood

Plant:  Apple (Miscellaneous Varieties)
Disease/Disorder:  Fertility Issues (Suspected)
Pathogen:  None
County:  Wood

Plant:  Apple (Miscellaneous Varieties)
Disease/Disorder:  Frogeye Leaf Spot (Suspected)
Pathogen:  Botryosphaeria obtusa
County:  Wood

Plant:  Apple (Miscellaneous Varieties)
Disease/Disorder:  Sooty Blotch
Pathogen:  Miscellaneous sooty blotch fungi
County:  Wood

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Hosta
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Columbia

Plant:  Hosta
Disease/Disorder:  Foliar Nematode
Pathogen:  Aphelenchoides sp.
County:  Columbia

Plant:  Hosta
Disease/Disorder:  Southern Blight
Pathogen:  Athelia rolsii
County:  Dane

Plant:  Iris (German Bearded)
Disease/Disorder:  Bacterial Soft Rot
Pathogen:  Pectobacterium sp.
County:  Burnett

Plant:  Wild Petunia
Disease/Disorder:  Rust
Pathogen:  Puccinia lateripes
County:  Marathon

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Fir (Fraser)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogen:  Rhizosphaera sp.
County:  Adams

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

Plant:  Spruce (Black Hills)
Disease/Disorder:  Transplant Shock
Pathogen:  None
County:  Portage

Plant:  Spruce (Unspecified)
Disease/Disorder:  Spruce Needle Drop
Pathogen:  Setomelanomma holmii
County:  Fond du Lac

(Back To Menu)

---

Vegetable Crops

Plant:  Potato 
Disease/Disorder:  Gray Mold
Pathogen:  Botrytis sp.
County:  Waushara

Plant:  Potato 
Disease/Disorder:  White Mold
Pathogen:  Sclerotinia sclerotiorum
County:  Waushara

Plant:  Pumpkin
Disease/Disorder:  Bacterial Wilt
Pathogen:  Erwinia tracheiphila
County:  Kenosha

Plant:  Pumpkin
Disease/Disorder:  Fusarium Crown Rot
Pathogen:  Fusarium sp.
County:  Kenosha

Plant:  Pumpkin
Disease/Disorder:  Powdery Mildew
Pathogen:  Oidium sp.
County:  Dane

Plant:  Tomato
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria lycopersici
County:  Vernon

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from August 16, 2025 through August 22, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Beech (American)
Disease/Disorder:  Chlorosis
Pathogen:  None
County:  Milwaukee

Plant:  Birch (Gray)
Disease/Disorder:  Chlorosis
Pathogen:  None
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (Bur)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Chlorosis
Pathogen:  None
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Dane

Plant:  Oak (Unspecified)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Door

Plant:  Oak (Unspecified)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
Counties:  Marathon, Sauk

Plant:  Pear (Callery)
Disease/Disorder:  Botryosphaeria Canker
Pathogen:  Botryosphaeria sp.
County:  Dane

Plant:  Pear (Callery)
Disease/Disorder:  Fire Blight
Pathogen:  Erwinia amylovora
County:  Dane

Plant:  Serviceberry
Disease/Disorder:  Chlorosis
Pathogen:  None
County:  Dane

Plant:  Serviceberry
Disease/Disorder:  Powdery Mildew
Pathogen:  Oidium sp.
County:  Dane

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

(Back To Menu)

---

Field Crops

Plant:  Corn (Field)
Disease/Disorder:  Southern Corn Rust
Pathogen:  Puccinia polysora
Counties:  Columbia, Grant, Iowa, Rock

Plant:  Corn (Field)
Disease/Disorder:  Tar Spot
Pathogen:  Phyllachora maydis
Counties:  Columbia, Grant, Iowa, Rock

(Back To Menu)

---

Forage Crops

Plant:  Alfalfa
Disease/Disorder:  Root Rot
Pathogen:  Aphanomyces euteiches, Phytophthora sp., Pythium sp., Rhizoctonia sp., Fusarium sp.
County:  Manitowoc

(Back To Menu)

---

Fruit Crops

Plant:  Cranberry
Disease/Disorder:  Bitter Rot
Pathogen:  Colletotrichum gloeosporioides/Glomerella cingulata
County:  Monroe

Plant:  Grape
Disease/Disorder:  Black Rot
Pathogen:  Phyllosticta ampelicida
County:  Dane

Plant:  Grape
Disease/Disorder:  Powdery Mildew
Pathogen:  Oidium sp.
County:  Dane

Plant:  Grape
Disease/Disorder:  Sour Rot
Pathogen:  Miscellaneous yeasts
County:  Dane

Plant:  Peach
Disease/Disorder:  Bacterial Canker
Pathogen:  Pseudomonas syringae
County:  Dane

Plant:  Peach
Disease/Disorder:  Cold Injury (Suspected)
Pathogen:  None
County:  Dane

Plant:  Raspberry
Disease/Disorder:  Root/Crown Rot
Pathogens:  Phytophthora sp., Rhizoctonia sp.
County:  Dane

Plant:  Strawberry
Disease/Disorder:  Root/Crown Rot
Pathogen:  Rhizoctonia sp.
County:  Dane

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Amaranth
Disease/Disorder:  Root/Crown Rot
Pathogen:  Pythium sp.
County:  Vernon

Plant:  Gaillardia
Disease/Disorder:  Aster Yellows (Suspected)
Pathogen:  Aster Yellows Phytoplasma
County:  Dane

Plant:  Hosta
Disease/Disorder:  Root/Crown Rot
Pathogen:  Fusarium oxysporum
County:  Waukesha

Plant:  Phlox
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp. 
Counties:  Bayfield, Brown

Plant:  Phlox
Disease/Disorder:  Powdery Mildew
Pathogen:  Oidium sp. 
County:  Brown

Plant:  Sunpatiens
Disease/Disorder:  Herbicide Damage (Suspected)
Pathogen:  None
County:  Brown

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

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

Plant:  Juniper
Disease/Disorder:  Winter Burn
Pathogen:  None
County:  Waukesha

Plant:  Larch (Unspecified)
Disease/Disorder:  Larch Needle Cast
Pathogen:  Mycosphaerella laricina
County:  Dane

(Back To Menu)

---

Vegetable Crops

Plant:  Broccoli
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp., Phytophthora sp., Fusarium oxysporum
County:  Milwaukee

Plant:  Cabbage (Napa)
Disease/Disorder:  Head Rot
Pathogen:  Rhizoctonia sp., Phytophthora sp.
County:  Milwaukee

Plant:  Corn (Sweet)
Disease/Disorder:  Gray Leaf Spot
Pathogen:  Cercospora sp.
County:  Door

Plant:  Kale
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp., Phytophthora sp., Fusarium sp.
County:  Milwaukee

Plant:  Pepper
Disease/Disorder:  Root Rot
Pathogen:  Pythium sp., Phytophthora sp., Fusarium sp.
County:  Milwaukee

Plant:  Potato
Disease/Disorder:  Black Leg
Pathogen:  Pectobacterium carotovorum subsp. carotovorum
County:  Waushara

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

Mushroom ID:  Jack O’Lantern Mushroom (Omphalotus illudens) 
County:  Dane

(Back To Menu)

---

 

Compiled by Brian Hudelson and Dante Tauscheck

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from August 9, 2025 through August 15, 2025.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Aspen 
Disease/Disorder:  Marssonina Leaf Spot and Blight
Pathogen:  Marssonina sp.
County:  Dane

Plant:  Cherry (Black)
Disease/Disorder:  Cold Injury (Suspected)
Pathogen:  None
County:  Dane

Plant:  Crabapple 
Disease/Disorder:  Sphaeropsis Canker
Pathogen:  Sphaeropsis sp.
County:  Dane

Plant:  Lilac (Unspecified)
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Waukesha

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

Plant:  Maple (Unspecified)
Disease/Disorder:  Melanconis Canker
Pathogen:  Melanconis sp.
County:  Dane

Plant:  Maple (Unspecified)
Disease/Disorder:  Sunburn
Pathogen:  None
County:  Jefferson

Plant:  Ninebark
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Crawford

Plant:  Ninebark
Disease/Disorder:  Cercospora Leaf Spot
Pathogen:  Cercospora sp.
County:  Crawford

Plant:  Oak (Bur)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
County:  Dane

Plant:  Oak (White)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
Counties:  Dane, Lake (IL)

Plant:  Oak (White)
Disease/Disorder:  Chlorosis
Pathogen:  None
Counties:  Dane, Lake (IL)

Plant:  Oak (White)
Disease/Disorder:  Monochaetia Leaf Spot
Pathogen:  Monochaetia sp.
County:  Lake (IL)

Plant:  Oak (White)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
Counties:  Dane, Lake (IL)

Plant:  Oak (Unspecified)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Winnebago

Plant:  Oak (Unspecified)
Disease/Disorder: Chlorosis
Pathogen:  None
County:  Winnebago

Plant:  Oak (Unspecified)
Disease/Disorder:  Monochaetia Leaf Spot
Pathogen:  Monochaetia sp.
County:  Winnebago

Plant:  Oak (Unspecified)
Disease/Disorder:  Oak Wilt
Pathogen:  Bretziella fagacearum
Counties:  Dane, Marathon

Plant:  Oak (Unspecified)
Disease/Disorder:  Smooth Patch
Pathogen:  None
County:  Dane

Plant:  Oak (Unspecified)
Disease/Disorder:  Tubakia Leaf Spot
Pathogen:  Tubakia dryina
County:  Winnebago

Plant:  Ohio Buckeye
Disease/Disorder:  Edema
Pathogen:  None
County:  Dane

Plant:  Redbud
Disease/Disorder:  Cold Injury (Suspected)
Pathogen:  None
County:  Dane

Plant:  Sumac (Fragrant)
Disease/Disorder:  Fusarium Wilt
Pathogen:  Fusarium sp.
County:  Waukesha

(Back To Menu)

---

Field Crops

Plant:  Corn (Field)
Disease/Disorder:  Southern Corn Rust
Pathogen:  Puccinia polysora
Counties:  Brown, Outagamie

Plant:  Wheat
Disease/Disorder:  Head Weathering
Pathogen:  Miscellaneous fungi
County:  Sheboygan

(Back To Menu)

---

Forage Crops

Plant:  Alfalfa
Disease/Disorder:  Bacterial Wilt
Pathogen:  Clavibacter michiganensis subsp. insidiosus
County:  Manitowoc

Plant:  Alfalfa
Disease/Disorder:  Root Rot
Pathogen:  Rhizoctonia sp., Fusarium sp.
County:  Manitowoc

(Back To Menu)

---

Fruit Crops

Plant:  Blueberry
Disease/Disorder: Chlorosis
Pathogen:  None
County:  St. Croix

Plant:  Blueberry
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  St. Croix

Plant:  Blueberry
Disease/Disorder:  Transplant Shock (Suspected)
Pathogen:  None
County:  Dane

Plant:  Grape
Disease/Disorder:  Black Rot
Pathogen:  Phyllosticta ampelicida
County:  Dane

Plant:  Plum
Disease/Disorder:  Black Knot
Pathogen:  Apiosporina morbosa
County:  Iowa

Plant:  Strawberry
Disease/Disorder:  Root/Crown Rot
Pathogens:  Phytophthora sp., Rhizoctonia sp.
County:  St. Croix

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Coral Bells
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Boone (IL)

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

Plant:  Veronica
Disease/Disorder:  Septoria Leaf Spot
Pathogen:  Septoria sp. 
County:  Winnebago

Plant:  Zinnia
Disease/Disorder:  Bacterial Leaf Spot
Pathogen:  Xanthomonas campestris pv. zinniae
County:  Bayfield

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

Plant:  Juniper
Disease/Disorder:  Diplodia Shoot Blight and Canker
Pathogen:  Diplodia sp.
County:  Waukesha

Plant:  Juniper
Disease/Disorder:  Winter Burn
Pathogen:  None
County:  Jefferson

(Back To Menu)

---

Vegetable Crops

Plant:  Asparagus
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  Waushara

Plant:  Asparagus
Disease/Disorder:  Root Rot
Pathogen:  Fusarium sp.
County:  Waushara

Plant:  Cucumber
Disease/Disorder:  Alternaria Leaf Spot
Pathogen:  Alternaria sp.
County:  Adams

Plant:  Cucumber
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum orbiculare
County:  Adams

Plant:  Snap Bean
Disease/Disorder:  Root Rot
Pathogens:  Aphanomyces sp., Fusarium sp.
County:  Oconto

Plant:  Snap Bean
Disease/Disorder:  Halo Blight
Pathogen:  Pseudomonas savastanoi pv. phaseolicola
County:  Manitowoc

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---