Parasitic growth on ash tree - Ask Extension
My Autum purple ash tree has something that looks like a parasitic growth. I include a photo here. Can you tell me what this parasite is? Is it harmfu...
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Parasitic growth on ash tree #880345
Asked August 06, 2024, 12:22 AM EDT
My Autum purple ash tree has something that looks like a parasitic growth. I include a photo here. Can you tell me what this parasite is? Is it harmful to the tree,? What is the best treatment to eliminate or minimize effects of this parasite on the tree?
Larimer County Colorado
Expert Response
Hi Rich,
Thanks for your question. This is ash flower gall and it's caused by eriophyid mites (teeny tiny "walking carrots") that feed within the bud in early spring. The feeding causes these galls, which look alarming, but are completely harmless to the tree.
Treatment is usually not warranted, nor necessary. The galls may persist in the tree for a couple years and if they are bothersome, you can prune them out.
Here's some more information from the University of Wisconsin: https://hort.extension.wisc.edu/articles/ash-flower-gall/
Thanks for your question. This is ash flower gall and it's caused by eriophyid mites (teeny tiny "walking carrots") that feed within the bud in early spring. The feeding causes these galls, which look alarming, but are completely harmless to the tree.
Treatment is usually not warranted, nor necessary. The galls may persist in the tree for a couple years and if they are bothersome, you can prune them out.
Here's some more information from the University of Wisconsin: https://hort.extension.wisc.edu/articles/ash-flower-gall/
Hello Alison,
Thanks for your quick response to my question.... which looks precisely answered as Ash Flower Gall. I'll try to use Sevin next spring to see if I can deter the gall formation compared to this year. Sure glad that it does not harm the tree. I love the shade from this tree and would hate to lose it.
God bless,
Rich
On Tuesday, August 6, 2024 at 02:15:27 PM MDT, Ask Extension <<personal data hidden>> wrote:
