Sick 'October Glory' Maple

[under_the_hill]

Had a call to look at a sick 'October Glory' Maple. Four of these trees were planted on a property in a large development about 5-7 year ago to replace Elms (or possibly Zelkovas) which weren't doing well. Two planted one year, two planted the next year.

Main tree pictures are the worst of the four. Two show no symptoms. One is showing some of the leaf symptoms and minor leaf drop. Spacing is about 50 feet from one tree to the next. Lawn irrigation runs 3x weekly to water bermuda lawn.

Leaves started dropping 2-3 weeks ago. Last year this tree went into the fall with nice red leaves.

I have a disease in mind, but I don't want to sway anyone who is willing to take a look one way or another. Any help or suggestions for definitive testing would be appreciated.

 

[PJM]

That one picture of the small branch looks like there was an old scale infestation. Otherwise, looks like leaf scorch.

 

[under_the_hill]

Thanks PJM. What bothers me is the way the leaf veins are necrotic further back than the dead edges of the leaves which I don't see in any pictures of leaf scorch. Also, the lawn irrigation should be keeping this tree well-watered. It looks more like Anthracnose to me. Is that possible to get mid-season? This area has been for several weeks upper 80s to low 90s with a lot of overcast days where it rains some, but not a lot.

 

[PJM]

Anthracnose is definitely more common in spring and early summer, maybe even into mid-summer depending on weather. Your state extension office may have a diagnostic clinic to test for the presence of the anthracnose fungi.

 

[under_the_hill]

Thanks again. I spoke to someone at a local arboretum and he felt it was likely Anthracnose and also gave me the contact information for the extension diagnostic clinic.