Anybody got a clue about this disease?

[bitternut]

This yard Maple in Western NY has spots on all its leaves like the ones in the picture. The tree is about 50 ft. tall and probably 40 or so years old. I think it is some type of Norway maple but I am not sure. All the leaves from top to bottom have spotting. It appears to start out as yellow spots which then get the black spotting. The tree appears healthy except for the spots. Do you have any idea what this could be?

[bitternut]

Here is the picture that was supposed to be with my post on maple tree leaf spots.

[Tom]

I don't want to supplant any new answers but thought you might be interested to know that we've been here before.

Check out this link
http://www.forestryforum.com/cgi-bin/board/YaBB.pl?board=Business;action=display;num=991180254;start=10

for Jeff's question about the very same Maple problem in his yard.  You'll find it interesting.

[Ron Scott]

I assume that these become big, blotchy black spots on the  maple leaves. It appears to be the fungal disease appropriately called "tar spot". It is a relatively harmless fungal disease.

It can only survive in clean air. It is unsightly, but you have clean air. The fungus is rare in urban and industrial areas because it is sensitive to pollution.

[bitternut]

Yep........You guys nailed it. I did a search for tar spots on maples and found lots of pictures and info that seems to confirm it is tar spot. Never heard of it or saw it before. Can't wait to tell my neighbor that he is going to have to rake and burn his leaves this fall. He will be estatic I'm sure. Thanks for the help.

[Shotgun]

Check this link out for lots of info on tar spot.

http://www.msue.msu.edu/ipm/CAT02_land/L08-09-02.htm#4

It's also a good site for insect and disease info other than tar spot.          

[Jeff]

The picture in my thread was much prettier.