Apple Leaf Spots

The attached pic is of a young apple tree leaf with some dark spots. These are on a friend’s newly planted apple tree, and they asked me if I could ID the spots, which I couldn’t. So I was hoping someone here might have an idea of what they could be. The dark spots do not wash/rub off, and do not seem to go all the way thru the leaf. There also is no visible insect damage with them.

Any ideas?

Screenshot_20210731-132900_Gallery

I can’t tell from the picture. Could you post more pictures preferably larger ones with more resolution. A couple of leaves with different numbers of spots, a pic of the bottom of one leaf that is effected, and a pic of the overall tree would be great. What is the apple cultivar (variety) and roostock if known as well as the state and hardiness zone the tree is located in.

I will ask for some more pics. I got one higher res one, but it is too big to upload. Will post those new ones when I get them.

I can answer the other q’s. These are trees which I grafted for the friend this spring. Root stock is Antonovka, variety is Mantet. They are being grown at ~8900’ in the Colorado Front Range. I have not seen them recently but probably about 2’ tall (assuming they are similar in size to mine which were grafted at the same time). They are probably in zone 4b (a bit colder than my place which is 5a).

1 Like

Here are those other shots, the whole tree, close-ups of the leaf top and bottom. Let me know if there is any more info which would help.

Screenshot_20210731-200237_Drive Screenshot_20210731-200249_Drive

Screenshot_20210731-200947_Drive

I am not sure what the condition is. I think we can eliminate a fair number of possible causes.

It isn’t one of the following:

Powdery Mildew
Fireblight
Frogeye leafspot
Alternaria leaf spot
Marssonina Blotch
Glomerella Leaf Spot

It doesn’t appear to be scab either. Mantet is scab susceptible but I don’t think the leaves have scab. I would expect to see something on the backs of the leaves and the lesions on the front to be larger with less distinct borders and more widely spaced spots on the leaves.

I would keep trying to identify the condition which may be difficult. I would also consider spraying the tree with a fungicide to prevent the condition from getting worse since I think it is likely to be some type of fungal infection.

Thanks mroot. Yeah, I was thinking of a round of copper spray of one “flavor” or another to try and cover fungal and bacterial possibilities.

I’m going to take a stab and say Cedar Apple Rust that just hasn’t turned rusty looking yet. I get it on some of my apple and pear leaves of certain varieties and sometimes it looks like that. Do you have any cedars near you?

Thanks Calvin. Yes my friend reports there are cedars (junipers) nearby. So that is a likely diagnosis. Copper spray still sounds like the right course of action.