Needlecast treatment on my Spruces - Ask Extension
I have several spruces that are losing their needles. I was told it is rhizosphaera needle cast disease. I hired a tree service who is spraying them 3...
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Needlecast treatment on my Spruces #869880
Asked May 24, 2024, 8:17 AM EDT
I have several spruces that are losing their needles. I was told it is rhizosphaera needle cast disease. I hired a tree service who is spraying them 3x a summer. The equipment they use misses the top 30% of the tree. They tell me this is fine, but being a gardener and having sprayed many plants in my life, that seems wrong. In fact everything I’ve read about this disease, the fungicide needs to be sprayed on all the new growth. Can you give your opinion and also be honest on the success of these treatments.
Lapeer County Michigan
Expert Response
Hi Patricia,
Good observation! I'm glad you are being thorough in researching the treatments on your trees.
Needlecast is generally an issue where growth is thick, and moisture that prompts the fungal pathogen can collect on the needles. Because the tops of the tree generally receive full sun, and plenty of wind to dry the needles, needlecast is generally not an issue in that region of the tree.
I can not speak to the efficacy of not treating the top 30% of the tree. But I can confirm that we generally do not see needlecast affecting the uppermost crown of blue spruce trees.
I hope this helps. Please let me know if you have any questions.
Thank you,
-Julie
Good observation! I'm glad you are being thorough in researching the treatments on your trees.
Needlecast is generally an issue where growth is thick, and moisture that prompts the fungal pathogen can collect on the needles. Because the tops of the tree generally receive full sun, and plenty of wind to dry the needles, needlecast is generally not an issue in that region of the tree.
I can not speak to the efficacy of not treating the top 30% of the tree. But I can confirm that we generally do not see needlecast affecting the uppermost crown of blue spruce trees.
I hope this helps. Please let me know if you have any questions.
Thank you,
-Julie
