Question

Picture of Leaf   QUESTION: Hello,
I recently planted (about a year ago) sour orange trees to make a hedge. I noticed recently (soon as it got cooler out), some leaves have this white frost like fungus on some of the leaves. Is this normal or a disease?

ANSWER: Jeremy:
Does this coating look "fuzzy" or waxy like? Has the tree been sprayed with anything? Do all of the leaves have this coating? Does this coating rub off with a piece of dry paper towel?

This does not look like a disease. Let me know the answers to the questions above to give me a better idea.

Steve

---------- FOLLOW-UP ----------

QUESTION: Morning Steve,
Thanks for getting back to me. Coating looks fuzzy. It is not waxy. Tree has not been sprayed with anything at all. Not all the leaves have this.

I had a friend also take a look at it and he said it might be salt from the ground. I live in AZ where the soil is awful and the salt might be extracting through the leaves.

Is that possible or what other thing may it be?

Answer
Jeremy:
If it is "fuzzy" there is a remote chance it could be a fungus called powdery mildew, however this fungus usually looks like "fuzzy patches or blotches" on the leaf.  Yours looks like most of the leaf is covered.  Powdery mildew usually makes the leaves turn yellow and fall early as well.  I am leaning toward something else.  You may consider carrying a couple of these leaves to your local garden center or nursery to get their comments. Best to pick a local small garden center that sells citrus rather than one of the gigantic box stores to ask.  You will have a better chance of getting an accurate ID from a family owned type business.

Steve