Plant and Insect Diagnostic Clinic Update – August 25, 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 linked.


Plant Diseases and Insect Damage


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


Broadleaf Trees


Bur oak, Two lined chestnut borer  


Bur oak, Bur oak blight



Symptoms of Verticilllium wilt in coneflowers
Symptoms of Verticilllium wilt in coneflowers

Various Oaks, anthracnose, Eriophyid mite galls, powdery mildew, oak bullet galls, oak tatters, Botryosphaeria twig blight


Pin oak, vein pocket gall


Maple, transplanting stress, for newly planted trees care keep in mind the recommendation on the publication Community Tree Planting and Care Guide


White Ash, Verticillium wilt 


Coniferous Trees


Pine, Pine wilt, Woodboring insect damage


Scotch Pine, Zimmerman pine moth damage 


Spruce, Rhizosphaera needle cast, Stigmina needle cast, Spruce needle miner, Phyllosticta needle blight



Signs (fungal structures) of Verticilllium wilt in coneflowers
Signs (fungal structures) of Verticillium wilt in culture. On the right, cells starting to form sclerotia -resting structure

Crabapple, Cedar apple rust 


Perennials and Annuals


Coneflower, Verticillium wilt   


Hosta, sunscald 


Dogwood, Dogwood Leaf Spot


Highbush Cranberry, Anthracnose 


Willow, Botryosphaeria canker 


Turf


Lawn, Nigrospora blight, establishment issues


Turfgrass, Ascochyta leaf blight 


Vegetables


Bell Pepper, Sunscald, Blossom end rot 


Fruit (small and tree fruit, including hops)


Hops, Alternaria cone disorder 


Ornamental Pear, suspected fungal cankers 


Cherry, suspected decline. see publication Understanding Decline in Trees 


 


Household and Other Insect Pests


Wood cockroach 


Larder beetles


 


Plant Identification


Quackgrass, see the article Quackgrass was the big winner in drought

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...