Question 453732: Reply to Response by Expert
Does the University of Minnesota Extension have a service that would come to our yard to diagnose the possibility of Rhizophaera needle cast? Or do you know of a service that will diagnose and, if spraying is necessary, spray?
Anoka County Minnesota
- Chlorothalonil can be sprayed twice in the spring to protect new needles. The first spray should be applied when needles are half the length of the mature needles. A second spray should be applied 3-4 weeks later or as prescribed on the fungicide label. Read and follow all instructions on the label when applying a fungicide!
- Before spraying fungicide, confirm that Rhizosphaera is the fungal pathogen causing damage by sending a lab sample to the University of Minnesota plant disease diagnostic clinic. Several other fungi result in symptoms very similar to Rhizosphaera.