Plant and Insect Diagnostic Clinic Update - June 4, 2008

Diseases and Disorders

  • Hackberry leaf drop has been reported again this spring in some parts of Iowa. We still are uncertain why hackberry trees will start to put on leaves and then drop them. We have observed that the trees do recover and put on a new flush of leaves and look fine by mid-summer. See the May 15, 1998 HHPN for more information.


  • Now is the time to begin looking for bagworms. Newly emerged bagworm caterpillars will be very small (as little as one-quarter inch) and the cases they construct of silk and plant foliage will camouflage into the trees and be difficult to see. Check trees that were infested in past and treat when new caterpillars appear. See the June 20, 2007 HHPN for more information. 
  • Spider mites are very common on some garden plants such as phlox. As we get to the warmer (and possibly drier!) part of the summer, check for early symptoms such as leaf bronzing. Treat with insecticidal soap, paying particular attention to thorough treatment of leaf undersides.
  • Carpenter bees continue to annoy homeowners in southern Iowa by drilling into exposed bare wood. See the June 7, 2002 HHPN for more details. 

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