Compiled by Brian Hudelson and Hulubanche Kassa

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from June 27, 2026 through July 3, 2026.

 

 

---

Broad-Leafed Woody Ornamentals

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

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

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

Plant:  Oak (White)
Disease/Disorder:  Root Rot
Pathogen:  Phytophthora sp.
County:  Waukesha

Plant:  Oak (Unspecified)
Disease/Disorder:  Wood Rot
Pathogen:  Bondarzewia berkeleyi
County:  Marathon

Plant:  Redbud
Disease/Disorder:  Eutypella Canker
Pathogen:  Eutypella sp.
County:  Milwaukee

Plant:  Rose-of-Sharon
Disease/Disorder:  Virus Disease (Suspected)
Pathogen:  Unspecified virus
County:  Dane

(Back To Menu)

---

Field Crops

Plant:  Corn
Disease/Disorder:  Eyespot
Pathogen:  Kabatiella zeae
County:  Richland

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

Fruit Crops

Plant:  Apple
Disease/Disorder:  Armillaria Root Disease (Suspected)
Pathogen:  Armillaria sp.
County:  Calumet

Plant:  Apple
Disease/Disorder:  Diaporthe Canker
Pathogen:  Diaporthe sp.
County:  Calumet

Plant:  Apple
Disease/Disorder:  Root/Crown Rot
Pathogens:  Phytophthora sp., Fusarium sp.
County:  Calumet

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

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

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Canada Wild Ginger
Disease/Disorder:  Bacterial Leaf Spot
Pathogen:  Xanthomonas sp.
County:  Green

Plant:  Geranium (Wild)
Disease/Disorder:  Bacterial Blight
Pathogen:  Xanthomonas sp.
County:  Green

(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:  Phomopsis Tip Blight
Pathogen:  Phomopsis juniperovora
County:  Waukesha

Plant:  Pine (Austrian)
Disease/Disorder:  Dothistroma Needle Blight
Pathogen:  Dothistroma sp.
County:  Ozaukee

Plant:  Pine (White)
Disease/Disorder:  Blue Stain
Pathogen:  Unspecified blue stain fungus
County:  Dane

Plant:  Pine (White)
Disease/Disorder:  Diplodia Shoot Blight and Canker
Pathogen:  Diplodia sp.
County:  Dane

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

Plant:  Spruce (Norway)
Disease/Disorder:  Winter Burn
Pathogen:  None
County:  Waukesha

Plant:  Spruce (White)
Disease/Disorder:  Rhizosphaera Needle Cast
Pathogen:  Rhizosphaera kalkhoffii
County:  Dane

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

(Back To Menu)

---

Vegetable Crops

Plant:  Potato
Disease/Disorder:  Bacterial Soft Rot
Pathogen:  Pectobacterium carotovorum subsp. carotovorum
County:  Portage

Plant:  Potato
Disease/Disorder:  Root Rot
Pathogen:  Rhizoctonia sp.
County:  Portage

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

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

(Back To Menu)

---

Field Crops

Plant:  Soybean
Disease/Disorder:  Seed Rot/Seedling Blight
Pathogen:  Phytophthora sp., Fusarium oxysporum
County:  Winnebago

(Back To Menu)

---

Forage Crops

No New Diseases

(Back To Menu)

---

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

(Back To Menu)

---

Herbaceous Ornamentals

No New Diseases

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

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

(Back To Menu)

---

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

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---

 

Compiled by Brian Hudelson and Hulubanche Kassa

The following diseases/disorders were identified at the Plant Disease Diagnostics Clinic from June 13, 2026 through June 19, 2026.

 

 

---

Broad-Leafed Woody Ornamentals

Plant:  Beech (European)
Disease/Disorder:  Botryosphaeria Canker
Pathogen:  Botryosphaeria sp.
County:  Waukesha

Plant:  Beech (European)
Disease/Disorder:  Phytophthora Canker
Pathogen:  Phytophthora sp.
County:  Waukesha

Plant:  Forsythia
Disease/Disorder:  Cold Injury
Pathogen:  None
County:  Crawford

Plant:  Ginkgo
Disease/Disorder:  Herbicide Damage
Pathogen:  None
County:  Calumet

Plant:  Lilac (Japanese Tree)
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum gloeosporioides
County:  Milwaukee

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

Plant:  Lilac (Shrub)
Disease/Disorder:  Bacterial Blight
Pathogen:  Pseudomonas syringae pv. syringae
County:  Crawford

Plant:  Lilac (Shrub)
Disease/Disorder:  Cold Injury
Pathogen:  None
County:  Crawford

Plant:  Maple (Norwegian Sunset)
Disease/Disorder:  Verticillium Wilt
Pathogen:  Verticillium sp.
County:  Sheboygan

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

Plant:  Maple (Silver)
Disease/Disorder:  Alternaria Leaf Spot
Pathogen:  Alternaria sp.
County:  Milwaukee

Plant:  Maple (Silver)
Disease/Disorder:  Anthracnose
Pathogen:  Discula sp.
County:  Milwaukee

Plant:  Oak (Regal Prince)
Disease/Disorder:  Herbicide Damage (Suspected)
Pathogen:  None
County:  Dane

Plant:  Willow (Pussy)
Disease/Disorder:  Anthracnose
Pathogen:  Colletotrichum sp.
County:  Crawford

Plant:  Willow (Pussy)
Disease/Disorder:  Monochaetia Leaf Spot
Pathogen:  Monochaetia sp.
County:  Crawford

(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:  Fire Blight
Pathogen:  Erwinia amylovora
County:  Waupaca

Plant:  Raspberry
Disease/Disorder:  Cane Blight
Pathogen:  Leptosphaeria (Paraconiothyrium) coniothyrium
County:  Dane

(Back To Menu)

---

Herbaceous Ornamentals

Plant:  Geranium (Wild)
Disease/Disorder:  Bacterial Blight
Pathogen:  Xanthomonas sp.
County:  Green

(Back To Menu)

---

Houseplants

No New Diseases

(Back To Menu)

---

Needled Woody Ornamentals

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

Plant:  Arborvitae
Disease/Disorder:  Phyllosticta Needle Blight
Pathogen:  Phyllosticta sp.
County:  Dodge

Plant:  Spruce (Norway)
Disease/Disorder:  Fertility Issues (Suspected)
Pathogen:  None
County:  Ozaukee

Plant:  Spruce (Norway)
Disease/Disorder:  Phomopsis Canker
Pathogen:  Phomopsis sp.
County:  Ozaukee

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

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

Plant:  Spruce (Unspecified)
Disease/Disorder:  Winter Burn (Suspected)
Pathogen:  None
County:  Dane

(Back To Menu)

---

Vegetable Crops

Plant:  Tomato
Disease/Disorder:  Tomato Spotted Wilt
Pathogen:  Tomato spotted wilt virus
County:  Wood

(Back To Menu)

---

Specialty Crops

No New Diseases

(Back To Menu)

---

Miscellaneous

No New Entries

(Back To Menu)

---