Plant and Insect Diagnostic Clinic Update – August 11, 2017

News Article

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 cited.


Plant Diseases and Insect Damage



Cucumber anthracnose symptoms (top) and signs (bottom)
Cucumber anthracnose symptoms (top) and signs (bottom). Photo credit: Lina Rodriguez Salamanca, Iowa State University Plant & Insect Diagnostic Clinic.

The following highlights represent recent sample submissions from fruit, vegetables, and ornamental plants.  


Broadleaf Trees


Pin Oak, Oak Wilt


Bur oak, Bur Oak Blight


Pin Oak, Horned oak gall  


Catalpa, Suspected abiotic scorch


River Birch, suspected nutritional deficiency and decline. see Nutrient/Soil pH Imbalances


Maple, Wood boring insect damage


Magnolia, Verticillium Wilt


Walnut, walnut caterpillars


Coniferous Trees


Eastern White Pine, Phomopsis tip blight, see article from University of Illinois Extension  


Spruce, Rhizosphaera Needle Cast


Spruce, Black Hills Spruce, Pine, suspected abiotic disorder


Spruce, Spruce spider mite


Black Hills Spruce, Spruce, Stigmina needle cast


Perennials and Annuals


Marigold, blossom rot, botrytis blight. see Gray mold


Hosta, Fusarium crown and rot rot, bacterial soft rot  see Hosta Diseases and Pests -- Sustainable Urban Landscapes



Walnut caterpillars.
Walnut caterpillars.  Picture by Anne Winslow-Cook.

Turf


Lawn, Nigrospora blight  


Lawn, Curvularia leaf blight  


Lawn, establishment issues


Vegetables


Cucumber, anthracnose, see University of Minnesota article on cucurbit anthracnose


Tomato, Suspected Juglone toxicity, see University of Wisconsin article on Black Walnut Toxicity


 


Fruit (small and tree fruit, including hops)


Ornamental Pear, Fire Blight


Pear, Pear leaf blister mite


Apple, Apple Maggot damage  


Strawberry, Pythium root rot, Fusarium crown rot  


 


Household and Other Insect Pests


Strawberry root weevil


Lone star ticks


 

Authors: 

Lina Rodriguez Salamanca Extension Plant Pathologist and Diagnostician (Program Specialist II)

Dr. Lina Rodriguez Salamanca is an extension plant pathologist and diagnostician with the Iowa State University Plant and Insect Diagnostic Clinic, a member of the North Central Plant Diagnostic Network (NCPDN) and National Plant Diagnostic Net...