April 18, 2007

When Should I Spray Conifers for Needle Diseases?

Several fungal needle diseases of conifers require fungicide sprays for satisfactory control. Fungicides do not cure needles already infected, but they protect the newest growth as it emerges. Because the new growth emerges in the spring, the ideal time to spray conifers is coming up soon.

Plant Disease Clinic Update - April 18, 2007

Plant samples with the following problems have been received by the Plant Disease Clinic recently:

Botrytis gray mold on greenhouse geranium and tomato

Diplodia tip blight of Austrian pine

Dothistroma needle blight of Austrian pine