Plant and Insect Diagnostic Clinic Update - July 25, 2012

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.

 
Disease

 

The past two weeks we have seen a wide variety of veggies and ornamentals, some have been diagnosed with diseases and others are suffering from heat and scorch.

 


On the veggie side, we have seen potato infected with Verticillium wilt, bacterial wilt and gummy stem blight on cucurbits, and white mold on tomato.

 

Last week we also saw some Verticillium on blackberry and other woody ornamentals.

 

We have seen some aster yellows on echinaceae, rose mosaic virus, and sun scorch on hostas.

 

Bur oaks are showing bur oak blight symptoms now.

 

Insect

 

The Genista broom moth is not a familiar name that rolls off the tongue, nor is it a pest with which we have had much experience.  Yet, we occasionally get to use that name for a caterpillar that people find defoliating their baptisia plants.  See the photo below and BugGuide for photos and information.  Baptisia is one of several plants that the Genista broom moth caterpillars consume.  If control is warranted: Pick caterpillars off by hand and discard; spray with Bacillus thuringiensis product such as Dipel while caterpillars are small; spray with general garden insecticide such as Sevin or permethrin or bifenthrin. Caterpillars are probably not fatal to otherwise healthy plants. The plants just look bad!

 

 

Genista broom moth caterpillar and damage to Baptisia foliage.Genista broom moth caterpillar and damage to Baptisia foliage.

Authors: 

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