Plant and Insect Diagnostic Clinic Update - April 12, 2013

Have you missed us? With the growing season fast approaching we will be better about sending updates on the disease and insect problems we are seeing in the Clinic. 


Speaking of which, I am being buzzed by fungus gnats as I am typing this. We had a few potted plants in the clinic and that is where they have been coming from. Those of you starting plants indoors may be seeing some as well. They are small dark colored flies that are attracted to windows and lunches. 




Boxelder bugs are driving everyone a bit batty this year. Don't worry - they are not breeding in the walls. They have been in various hiding places all winter and the warmer weather causes them to become active and crawl around. There is no practical way to treat them and they are harmless. Problem should stop mid-April or so if we get nice warm weather.  Read more on the clinic website.




So far it appears it will be another tough year for evergreens. Most of what we are seeing on white pines, arborvitae, and yew is problems from the drought and heat (on top of the wet years that damaged roots). Blue spruce are also suffering from poor weather but are also prone to Rhizosphaera needle cast, Stigmina, and cytospora cankers. Also see article in this issue about winter desiccation.


If you are planning to treat for Rhizosphaera this is the time of year to start planning and watching for the new growth. We recommend treating when there is about an inch of new growth and then again about 4-6 weeks later (depending on how fast trees are putting on new needles). 


Visit the PIDC’s facebook page to ask questions and for updates and more pictures.




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