July 13, 2018

Plant and Insect Diagnostic Clinic Update – July 13, 2018


The following are highlights and updates about sample submissions from fruit, vegetables, and ornamentals, 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.

Green-Striped Mapleworm "Outbreak" in Buchanan County, 2018

Maple tree defoliated by green-striped mapleworm


Green-striped mapleworm caterpillars

Bagworms Have Hatched. Check Your Tree Now

Small bagworms on spruce tree


Picture 1. Small bagworms camouflage and may be hard to find.  Photo by Larry Ginger.

Alert and curious people in Iowa have noticed that the bagworm eggs have hatched and that the small, bag-carrying caterpillars are feeding on tree foliage.

Harvesting and Storing Melons


Watermelons, muskmelons, and honeydews are delicious summertime treats.  To obtain the best flavor, melons must be harvested at the right stage of maturity.  Once harvested, proper storage prolongs their storage life for as long as possible.  Guidelines for harvesting and storing watermelons, muskmelons, and honeydews are presented below. 

Tomato Pest and Disease


Tomatoes are the most popular garden vegetable crop in Iowa but hornworms and plant diseases may spoil the outlook for BLT sandwiches.  Learn more about common tomato problems in the Iowa State University Extension & Outreach Yard and Garden news release from July 12, 2018.

Iowa State Fair Weed ID Contest


Iowa State University Extension and Outreach will host its annual Iowa State Fair Weed Identification Contest on Friday, Aug. 10, from 9-11:30 a.m. in front of the John Deere Agriculture Building. Everyone can participate in one of three divisions: future agronomists (youth), general and professional. Winners will be announced at the 3 p.m.

All about Sweet Corn


Sweet corn fresh from the garden or farmers market is a tasty summer treat.  When to harvest, how to store and other details can make a difference in your sweet corn enjoyment.  Learn more sweet corn in the Iowa State University Extension & Outreach Yard and Garden news release from July 3, 2018.

Turfgrass Weeds


Our rainy spring weather was great for crabgrass and other weeds that grow in the home lawn.  Learn more about crabgrass and other weeds and various control measures to minimize weed populations in the Iowa State University Extension & Outreach Yard and Garden news release from June 28, 2018.

Updated Greenhouse Pesticide Applicator Certification Manual

Cover of Extension certification manual, Greenhouse Pest Managment

The newly revised and updated version of the Category 3 Greenhouse Pest Management – Iowa Commercial Pesticide Applicator Manual (CS 0015B) is available from Iowa State University