Plant and Insect Diagnostic Clinic Update – September 15, 2017

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.  



Tubakia leaf spot
Tubakia leaf spot in red oak. Top: foliar spots. Bottom and middle : signs of the pathogenat different ,agnifications

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 gal


Oak, lace bug damage


Crabapple, cedar apple rustsapsucker 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 cankerspider 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


Waterhemp


Snow-on-the-mountain, a poisonous plant to cattle



 


 


Authors: 

Lina Rodriguez Salamanca Extension Plant Pathologist and Diagnostician

Dr. Lina Rodriguez-Salamanca is an extension plant pathologist and diagnostician with the Iowa State University Plant and Insect Diagnostic Clinic  (clinic.ipm.iastate.edu), a member of the National Plant Diagnostic Network (NPDN,&nbsp...

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Horticulture and Home Pest News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on September 15, 2107. The information contained within may not be the most current and accurate depending on when it is accessed.