The following are highlights and updates about samples 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 (hyperlink) cited.
Plant Diseases and Insect Damage
The following highlights represent recent sample submissions from fruit, vegetables, and ornamental plants.
Broadleaf Trees
- Amur Maple, suspected decline, fungal canker
- Bur Oak, bur oak blight, oak tatters, oak bullet galls
- Red oak, tubakia leaf spot, wind damaged petioles
- Pin oak, oak vein pocket gall
- Oak, lace bug damage
- Crabapple, cedar apple rust, sapsucker damage, phoma leaf spot, scab
- Maple, decline, anthracnose, physiological scorch, iron deficiency, tar spot, aphids
- Birch, Septoria leaf spot
Coniferous Trees
- Black Hills Spruce, drought stress suspected
- Hemlock, rust mites
- Pine, Diplodia tip blight
- Spruce, Rhizosphaera needle cast, Stigmina needle cast, suspected fungal canker, spider mite damage
Perennials and Annuals
- Boxwood, Volutella canker, and leaf blight
- Serviceberry, lace bugs, rust
- Ninebark, spider mite damage
Turf
- Lawn, Curvularia leaf spot, leaf spot and melting out, anthracnose, rust
Vegetables
- Cucumber anthracnose
- Cantaloupe, Alternaria leaf blight
- Tomato, leaf mold, suspected magnesium deficiency
Fruit (small and tree fruit, including hops)
- Cherry, gummosis
- Apple, Cedar-apple Rust
- Grape, grape downy mildew, suspected black rot
- Blackberry, anthracnose
- Hops, Apple Mosaic Virus
Household and Landscape
- Yellowjacket wasps are active and causing concern as "bees" of autumn.
Plant ID
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