Black spots on maple leaves

[highlandcattle]

Has anyone been seeing large round flat black spots on their maple trees? Took samples to soil and water, they really didn't seem to know. One said pollution(?) another said blight(fungus). tried calling master gardner at cornell, no answer. I'm thinking becasue of the amount of rain we've had, something took over. HELP!!!

[DrTimPerkins]

Has anyone been seeing large round flat black spots on their maple trees? Took samples to soil and water, they really didn't seem to know. One said pollution(?) another said blight(fungus). tried calling master gardner at cornell, no answer. I'm thinking becasue of the amount of rain we've had, something took over. HELP!!!

Not much to go on with that description, but sounds like it could be Tar Spot.
http://www.ppdl.purdue.edu/ppdl/expert/Tar_Spot_on_Maple.html

[allgreenmaple]

Has anyone been seeing large round flat black spots on their maple trees? Took samples to soil and water, they really didn't seem to know. One said pollution(?) another said blight(fungus). tried calling master gardner at cornell, no answer. I'm thinking becasue of the amount of rain we've had, something took over. HELP!!! I think tar spot is spot on. I have a couple of soft maples by my garage, & that is likely what it is......Here is a pic http://search.yahoo.com/r/_ylt=A0oG7m2Ga5hO.3oA2h9XNyoA;_ylu=X3oDMTE0YWFkMWd uBHNlYwNzcgRwb3MDMwRjb2xvA2FjMgR2dGlkA1FJMDQwXzE5N g--/SIG=12hb0ithk/EXP=1318640646/**http%3a//www.ppdl.purdue.edu/PPDL/expert/Tar_Spot_on_Maple.html

[Michael Greer]

We just discovered the same thing In Potsdam NY, on a couple of Norway maples across the street. I have big Sugar maples nearby...does this set off any alarms in sugar country?

[Flat Lander Sugaring]

yes just today in burlington,vt. Almost every leaf had one it was really weird. I went back to the job site and the maple we had lunch under didnt have a one, about 1/2 mile apart from each other
I'll take a picture tomorrow and post it

[DrTimPerkins]

...does this set off any alarms in sugar country?

No, it is relatively common and not terribly stressful to the tree. May cause slightly faster leaf-drop, especially in Norway maple and when very heavy, but otherwise not a real problem.

[sugaringman85]

If it is on a norway maple it definately is tar spot and is extremely common in the northeast. usually it doesn't effect the tree to much. It is very uncommon in red and sugar maples though. usually with higher amounts of rain it tends to blow up and effect more of the tree. Not much you can do about it.

[RC Maple]

I'm glad someone else had this question. I noticed the black spots on my small silver maple behind the house. Now I know.