Red spots on silver maple leaf

[tonka]

Dose anyone know what is up with this silver maple leaf?2018020181

[maple flats]

I'm just guessing but I suspect it could be a fungus because of too much rain. I have not seen that before. does it rub off, or is it right in the leaves?

[tonka]

I think it can be rubbed off, we never tried. The red dose not show on the front of the leaf which I would assume that it is not a fungus.
The story behind the leaves is I dropped of some syrup at a greenhouse that sells my syrup and there was a gentalmen who brought the leaf in to have the owner of the greenhouse take a look at, just to see if it's a serious disease or if it's something not to worry about and none of us had a clue to what it was so I told them that I would post on here and see if anyone else has seen or know anything about the red dots.

[Pdiamond]

Do you know if all the leaves have the red coloring or are some of them black?

[DrTimPerkins]

Hard to tell from the photos, but I'd say EITHER maple gall mites (most likely maple velvet erineum gall--silver maple is a common host), some type of fungus, or a Mg deficiency (in that order). Get some better close ups of the red spots. Do they look like little bumps, or felt-like, or is the red area flat?

Fact sheet for galls at https://ohioline.osu.edu/factsheet/ENT-60

Not a lot you can do about it at this point, and not really anything to worry about. Mostly just looks strange.

[tonka]

They looked/felt like felt when I was observing the leaf. The gentleman who brought the leaf said that there were a couple branches with all the leaves like the leaf in the photo. The owner of the greenhouse ruled out that it was a fungus.

[DrTimPerkins]

It is most likely maple velvet erineum gall then. Velvet (felt-like) texture is diagnostic.

[tonka]

Thanks guys for the help in finding out what it is.