What are these spots on a maple tree?

[southern-ct-4]

Any idea what these are? Just noticed them yesterday, but not sure how long they've been there for. Seems to be on almost every leaf (at least the low ones that I can see). Tree is approx. 8 years old.

[MorpheusPA]

Look up a disease called Maple Leaf Tar Spot--and look at what it looks like in spring before it turns tarry.

Treatment is very simple; rake up the leaves next fall. Don't mulch, the leaves left on the soil will infect next year's crop of leaves. Removing them will remove the spores, which will solve (or at least severely reduce) the problem.

[bpgreen]

You've also got iron chlorosis (dark green veins with yellowish leaves), which is caused by a lack of available iron.

In my case, there is plenty of iron in the soil but ther ph is high enough that the tree can't use it. So the leaves can become bright yellow and eventually burn.

Your leaves don't look too bad, so you can probably just ignore it. But you can also use a foliar spray (as long as the technique is going to stay below 85 for a few days. Depending on your soil chemistry, you may be able to use chelated iron around the drip zone (edta works in some cases, but I need eddha). That will help longer than a foliar spray.

If the chlorosis is caused by high ph, you might be able to use a bulb auger to drill holes around the drip line and pour shoul sulfur in. That takes longer to work, but also lasts longer.

[southern-ct-4]

Thank you very much

[bpgreen]

Ugh. Stupid autocorrect. Soil sulfur. Not shoul sulfur.