Plant and Insect Diagnostic Clinic Update - September 13, 2013

 The following are highlights and updates about samples and questions recently received in the Plant & Insect Diagnostic Clinic. Visit the PIDC’s Facebook page to ask questions and for updates and more pictures.



Backswimmers are aquatic insects, but later in the year adults take to the air for mating and migration.  Often they can be found near lights. Backswimmers are harmless but can bite if handled.  See picture below.

Foreign grain beetles have been making an appearance the past few weeks.  These tiny beetles can be very numerous and found dead on windowsills and around sinks.  They are a harmless nuisance and tend to be more of a problem in newer homes and buildings.  No control is possible and they usually are only a problem for a short time period.

Praying mantids are certainly numerous this year.  Most are the Chinese mantid.  Milder winters increase survival of the overwintering egg cases and lead to larger populations the following summer.  For those looking to find one they can often be found near where there are outdoor lights at night.  They make interesting pests, but usually don't live more than a few months.

We have talked before about the so-called hummingbird moths -- the large sphinx moths that feed on nectar from fall flowers by hovering in a fashion reminiscent of the hummingbirds.  Below is a photo of the white-lined sphinx moth performing its hummingbird imitation while feeding on nectar from hosta flowers. The white-lined sphinx moth is the most common of the several species of moths you may see feeding on nectar at this time of year. Read more about the white-lined sphinx moth on BugGuide and see a photo of the white-lined moth caterpillar on purslane on the PIDC Facebook page. 


White-lined sphinx moth at hosta flower.White-lined sphinx moth at hosta flower.

Backswimmer.  Note the legs that are modified to function like oars.


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