Here's what the front side looks like.

Canaliy, what part of the country do you live in, you GW Zone field isn't filled out. Helps for us to know where you are. This looks to be something fungal to me. We don't have much fungal issues here in California, so I'm wondering if you're in a more humid area of the country by chance?

Patty S.

Hi Patty, sorry I'm a bit new. So I live in zone 6. Pittsburgh to be precise. Its a dwarf cultivar and I'm planning on bringing it indoors during the winter. It was outside in the nursery in which I purchased it and has been outside since I brought it home. We have been having a very humid summer here so possibly it's fungal?

Scary. Never seen that before. If it is fungal, try copper or organocide. But be careful with the copper not to use in conjunction with an oil. I dont know what that is though. You should bring it to your county extension office.

Canaliy, before you spray with copper, which can burn leaves if not applied at the correct dilution, I would contact your nursery right away, and ask them to ID the problem for you. If they cannot send your very good photos to local extension office to get an official diagnosis and proper treatment.

Patty S.

I worry that Canaliy isn't going to get great information from his/her local extension, not being from a citrus state. That's a good place to start, I guess, but I'd be sorely tempted to seek some REAL citrus experts.

In the meantime, call/contact the nursery from which you purchased this plant. If it is a mail-order tree, contact their customer service and ask to speak to a horticulturist/technician on staff. Email pictures...get answers.

Also, if mail-order, you might contact the extension office in THEIR county with your images.

Oh yeah....you HAVE to keep us up to date! ;-)

I dont know why people are so afraid to spray there trees. I have abused the crap out of my trees (not on purpose) just to watch them bounce back and grow beautifully. Try the copper on a SMALL AREA or JUST A COUPLE leaves first. No harm will come of it. If copper does not work, try something else. Organocide is organic and has helped my Citrus trees a ton. It might even be some kind of pest. Just dont overdo it and start with only a couple of leaves until you know how your tree will react. These trees have been around for thousands of years, a little copper isnt going to kill it. It might make the leaves drop if you spray too much so thats why you go small to begin with. Not everyone has the luxury or time to have such a good county extension office such as southern California.

Hey everyone thank you so much for the input. I took a sample of the leaf to my local nursery and not surprisingly they had no idea what it was( the person I took the sample to admitted he didn't know much about citrus) but they did give me the contact information from the distributor from which they received the plant and I've sent an email with picture asking them about it. I will keep you all posted about the results.

Thanks, Canaliy!

Very good point, Rhizo. Canaliy, try sending your photos to the University of Florida citrus folks. They should be able to ID this for you. I think this may be the very early stages of Greasy Spot, but since this is mainly a gulf coast issue, I'm no expert. The Florida Citrus folks can tell you for absolute sure.

Patty S.

Here is a link that might be useful: U of Florida: A Guide to Citrus Leaf Disease Identification

This is not any fungus I recognize. I suspect it is edema (oedema), a disorder caused by a plant becoming too dry, followed by very wet conditions. If so, there's nothing to "cure;" just try to keep the water availability more even to the plant.

Malcolm Manners
John and Ruth Tyndall Professor of Citrus Science
Florida Southern College

Thanks for coming to our rescue, Dr. Manners. It appeared to be fungal to me due to the symmetrical appearance of the rings, but then, we just don't get this kind of fungal growth here in S. Calif. Our fungus issues tend to happen during the winter months, and nothing really with citrus (roses, stone fruits, hibiscus.) Good to know it's just an uneven watering issue!

Patty S.