The following are highlights and updates about samples and questions recently received in the Plant & Insect Diagnostic Clinic:
Horray! It's cicada killer wasp season again. They are abundant at this time of the year (late July to frost, while the cicadas are out and buzzing in the trees).
The cicada killer wasp looks ferocious and menacing, but is not aggressive and not dangerous. In 34 years of talking to the public about the cicada killer wasp, I have heard from one person who was stung. That person picked it up to see what it was!
Control of cicada killers is not essential though most people chose to control them out of fear and annoyance. Put insecticide DUST into the burrow openings at night for best control results. See our online article for more information.
With all the attention to millipedes in this damp summer, we have had few calls about earwigs. That appears to have changed in the past week. See our online article for more information on earwigs.
Hot weather and high humidity have triggered some common diseases this time of the year. We have seen anthracnose on cucumbers, squash, and grapes. We are still hearing about tomatoes with Septoria leaf spot and recently received some samples with bacterial canker and spot (Sse article elsewhere in this issue). We had some turf and lawn samples with "air conditioner diseases" (Pythium blight and brown patch). B.O.B. (Burr oak blight) is also starting to show up!
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