Is there any fungicide which stops Rhizosphaera in Blue Spruce once a trees has it? - Ask Extension
I believe one of my Blue Spruce trees has a fungus (Rhizosphaera) which is causing the bottom branches/needles to die off. Is there a spray I can app...
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Is there any fungicide which stops Rhizosphaera in Blue Spruce once a trees has it? #764486
Asked July 28, 2021, 6:53 PM EDT
I believe one of my Blue Spruce trees has a fungus (Rhizosphaera) which is causing the bottom branches/needles to die off. Is there a spray I can apply to this tree to save it......or is too late? See attached photo.
How do I prevent this from attacking other Blue Spruce trees in my yard?
Will this fungus affect my cedar hedge?
Thanks for your assistance,
Jeff
Grand Isle County Vermont
Expert Response
Hi Jeffrey,
This could be rhizosphaera needlecast. It is listed as a pathogen on cedars but i have never seen it. This fungal disease has been on the increase and will cause dieback in the lower branches and work its way up the tree over the years with successive rains. Pruning off lower branches will help remove inoculum, but spraying trees is very difficult when it is large and it is expensive. Here is more info on the disease and its management: https://ag.umass.edu/landscape/fact-sheets/rhizosphaera-needle-cast
Ann Hazelrigg
Plant Pathologist
