Elm tree disease

Question

What kind of fungi is it? (Attached the image). Is there any treatment for it?
Thank you for the answers

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Answer 1

It's hard to see from the photo if it is powdery mildew (a fungal disease), or maybe giant white fly (an insect pest that puts out a cottony mass for self protection). If it's white fly you will see some white, winged fying insects in and about the white material.
If its' a large elm tree you will need to hire a tree service or pest control service with spray equipment. If it's small you can use 70% need oil sprayed every week until the problem clears up.

A tree or pest control service may use a more specific fungicide or insecticide for spraying or injecting, depending on their diagnosis.