Plant and Insect Diagnostic Clinic Update – April 27, 2018

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.

The following are plant diseases and insect damage highlights of last month's sample submissions from fruit, vegetables, and ornamentals.  

Plant Pest/Problem type Diagnosis (link to encyclopedia article)
Scarlet Oak Insect damage Woodborer activity in dead limb


Phyllosticta needle blight

Eastern White Pine














Suspected winter injury

 Winter injury symptoms

Scots Pine Insect damage Pine tortoise scale





watermold (Phytophthora) structures


Phytophthora crown rot and shoot blight

Crown rot symptoms (discolored areas)


Million Bells


Powdery mildew

Geranium Abiotics Suspected abiotic disorder









Botrytis fungal structures

Gray Mold -Botrytis Stem canker

Gray mold canker signs in tomato stem 

Tomato Abiotics Suspected injury
Green Bean Pathogens, Insect damage Thrips, Twospotted spider mites
Tomato Abiotics Suspected nutrient imbalance


Identification summary:

Service Pest Category Identification 
Insect ID  Arthropods Bed bug
Insect ID  Arthropods Multicolored Asian lady beetle
Plant ID  Plants/Weeds Insufficient sample
Plant ID  Plants/Weeds Common Chickweed
Plant ID  Plants/Weeds European black alder

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 April 27, 2018. The information contained within may not be the most current and accurate depending on when it is accessed.