The following are highlights and updates about samples and questions recently received in the Plant & Insect Diagnostic Clinic: Diseases
The PIDC is getting busy with this early spring! We have already received several plant problem samples and most of them are showing some sort of environmental damage. Most of them are evergreens (firs, arborvitae, and spruce) and we have diagnosed mostly with environmental stress, possibly due to dry weather conditions last year. Some spruces are also being sent to check for Rhizosphaera and Stigmina needlecast. Other interesting samples include indoor-grown ornamentals such as hosta and African violet showing virus-like symptoms.
Insect samples have started to increase. In addition to the fungus gnat "outbreak" reported earlier, samples of wolf spiders and other active hunting spiders have predominated. This should be a reminder to spend at least a little time this spring finding and sealing cracks and gaps through which spiders and other accidental invaders wander indoors by mistake. Reducing outdoor lighting at night that attracts the insects that attract the spiders can also help.
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