Plant and Insect Diagnostic Clinic Update – August 16, 2019

The following are highlights and updates about sample submissions for our different services (identification or Plant problem diagnosis from fruit, vegetables, and ornamentals), and questions recently received in the Plant and Insect Diagnostic Clinic. Visit the PIDC's Facebook page for updates and more pictures. For more information on a particular disease or insect problem listed, follow the article cited.

Plant Problem diagnosis  (with links to articles)

Host Category Plant Identification or Diagnosis
Coniferous trees Spruce Stigmina needle cast, suspected environmental stress, fungal cankers
Scots Pine Diplodia Tip Blight and Canker, suspected Pine wilt

Suspected environmental stress

Phyllosticta needle blight

Phomopsis tip blight

Broadleaf trees Eastern Redbud Transplant stress, Poor Planting Practices and Post-planting Care
ornamental pear Fire Blight
Ornamental prunus Black Knot
Crababple Scab
Lilac  Pseudocercospora Leaf Spot, Powdery Mildew
Magnolia Magnolia Scale

Girdling roots 

maple on the right thin canopy
Maple on the right with a thinning canopy

maple girdling roots choking the tree
Upon close inspection girdling roots choking the maple tree.

Willow  Willow anthracnose
Oak (various)

Bur Oak Blight, Anthracnose on shade trees,  

suspected wetwood or slime flux, Suspected Physiological scorch,

Bot twig canker, Tubakia leaf spot in Oaks, Oak decline

Japanese Beetle feeding damage

Fruit (small and tree) Apple  Cedar-Apple Rust
Japanese Beetle feeding damage
Phoma leaf spot
Suspected chemical injury, phytoplasma or virus
pear Pear rust and various fungal spots
Strawberry Phomopsis blight
Cherry suspected decline
Vegetables Garlic

Fusarium basal rot, Stem and Bulb nematode,

Bulb mites, Purple blotch

Kale Alternaria leaf spot
Muskmelon Alternaria spot and leaf blight 
Onion Soft rot 
Pepper Cutworm damage, Secondary soft rot
Tomato Bacterial canker, see Tomato Diseases and Disorders
Phytotoxicity suspected

Yellow shoulder 

Yellow Shoulder on Tomato Fruit
Yellow shoulder on tomato fruit

Leaf mold  

Suspected herbicide injury

Perennials and Annuals Sedum Pythium root rot
Clematis wilt/ blight 

Clematis wilt/ blight  

Clematis blight cause by the fungal pathogen Phoma clematidina
Clematis blight and leaf spot cause by the fungal pathogen Phoma clematidina

Turf/Lawn Various grasses Curvularia blight, anthracnose

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