Plant and Insect Diagnostic Clinic Update - December 9, 2009

The following are highlights and updates about samples and questions recently received in the Clinic:

Insects

Thousand cankers disease of black walnut is a mouthfull to say, but it is a new and potentially devastating disease of the black walnut tree, Juglans nigra.  Thousand canker disease is a newly recognized disease that has devastated black walnut trees in many towns in the western United States, from New Mexico to Idaho. For more information see the ISU Yard and Garden Column and the fact sheet from Colorado State University.

What to plant as replacements for ash trees is an important topic to consider as we anticipate the arrival of emerald ash borer into the state of Iowa.  See information from Jeff Iles in the ISU Yard and Garden Column.

Authors: 

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