August 25, 2017

Plant and Insect Diagnostic Clinic Update – August 25, 2017

Signs (fungal structures) of Verticilllium wilt in coneflowers

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.

Harvesting and Storing Winter Squash

Harvest winter squash when the fruit are fully mature.  Mature winter squash have very hard skins that can’t be punctured with the thumbnail.  Additionally, mature winter squash have dull-looking surfaces. 

When harvesting winter squash, handle them carefully to avoid cuts and bruises.  These injuries are not only unsightly, they provide entrances for various rot-producing organisms.  Cut the fruit off the vine with a pruning shears.  Leave a 1 inch stem on each fruit. 

Cottony Grass Scale – Interesting and Rare

Strips of brown grass between the tire tracks are a symptom of cottony grass scale

For only the second time within memory we have received a report of cottony grass scale, Eriopeltis festucae, damaging turfgrass in Iowa.  Our one previous experience was 8 years ago in 2009 and coincided with 4 years of reports in Minnesota.

Germinating Seeds For Future Growth

As fall approaches, it’s time to start thinking about gathering seeds for the upcoming growing season.  Some plants such as butterfly milkweed, Jack-in-the-pulpit and purple coneflower can be planted outdoors in the fall to germinate next spring, or you can start plants indoors over winter for next spring’s garden.  Learn more in the Iowa State University Extension & Outreach Yard & Garden news release from August 24, 2017.

Community Tree Steward Program Returns

Iowa State University Extension and Outreach is reviving its Community Tree Steward program, a seven-meeting course designed to train community members on proper selection, care and maintenance of trees.  Learn more about the Community Tree Steward Program in the Iowa State University Extension & Outreach news release from August 18, 2017.

How to Overseed a Lawn

Overseeding is one way to improve an existing lawn that is in poor condition. See the Iowa State University Extension and Outreach Yard & Garden news release from August 17, 2017 for information on how to overseed, what seed to use and how to ensure good germination.