How to treat Brown spots on Red Orange tree leaves?

Marylander2013

10 years ago

I'm growing a "Blood" Orange tree in a container in Maryland. Recently brown spots have appeared on 4 leaves. I tend to think that this is Alternaria.

It's important to stress that a few days ago (before the appearance of the Brown spots) I discovered Slugs in the container. At the beginning I sprayed the leaves with a product for "insect, disease and Mite control" (which contains Sulfur and Pyrethrins) . After I discovered that it doesn't kill Snails, I killed them with salt (around 3-4 tea spoons overall that didn't touch the leaves). The Brown spots appeared couple of days, after I applied Bayer's product and the salt.

My questions are:
1. Can it be the result of the product that contains Sulful and Pyrethrins?
2. Can it be the result of spreading the salt on the ground?
3. Is it Altenaria or is there another possibility?
4. What is the best solution for this situation?

I enclosed a picture of one of the leaves.

By the way, in order to make sure that there are no Slugs, I used now Elemntals Slug & Snail, and I hope it will prevent any more of them.

Comments (5)

jean001a
10 years ago
You can't treat those brown spots because some critter ate the surface of the leaf.

Those few spots are too few to be a problem. but keep watch for nibblers so that you can squish them before brown spots develop.;
jean001a
10 years ago
More info.
Stop spraying before you have a diagnosis. You're wasting time & money.

A question:
Why are you putting salt on the soil? (Even though I don't know the reason I do know that it won't help anything.)
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rhizo_1 (North AL) zone 7
10 years ago
"...it won't help anything " and I'll add that adding salt to the soil can be damaging.

And please....do not use any pesticide until you have carefully read and understood all of the directions. Also, home remedies shouldn't be used unless there is a good understanding of how they work, possible problems, and potential damage. Repeating jean again....don't use anything unless you know just what the problem is.
Marylander2013
Original Author
10 years ago
Thank you very much!
I'll wait and see if more brown spots develop. Till now, it looks like they don't. Following your advises, I'm not going to do anything for now.
Regarding the salt - I used it in order to kill Snails, which are the leaves, but I'm not going to that again.
jean001a
10 years ago
Flick the snails into soapy water. They will drown.