Citrus Tree Leaf Disease/Fungus

tdbrueggenApril 24, 2012

I've started to notice a sort of fungus or disease on the leaves of my Meyer Lemon and lime trees. It looks like a silvery squiggly trail, almost as if a snail has slid around on the leaf. After about two weeks the leaf will begin to roll up and die. I have been cutting off any leaf that I identify with it, trying to stop the spread, but I don't really know how it spreads. It only seems to be affecting new leaves. I've bought a fungicide but I really don't want to use it blindly, not knowing what I am treating. Does anyone know what it is? I've researched citrus tree fungus/disease, but I can't find anything that describes what this looks like. Any thoughts? I really need to figure it out!

Thank you for reporting this comment. Undo
hoosierquilt USDA 10A Sunset 23 Vista CA

Citrus Leafminer. It's not a fungus, it is the larvae of the CLM moth, mining through the leaf. Don't cut off the leaves, your tree needs them to respirate. If you feel compelled to treat, the best and safest treatment is a combination of Spinosad and Neem or Volk Oil (to help it stick better, and to smother the adult moths). Be sure to spray in the evening, when the bees have gone back in the hive, and if possible, to spray before blossoms appear. You can spray every 3 weeks for 3 apps. You may need to do a series of sprayings again, in the late summer/early fall, when they tend to come back in your area. Here for us in Calif., we only tend to see them in the summer, so I try to start spraying in July. Last caveat - don't use the hort oils if your temps are above 85 degrees, as you'll fry your leaves. Most folks opt not to treat, as this is mainly a cosmetic issue, unless you have very young trees and high disease pressure.

Patty S.

Here is a link that might be useful: UC IPM: Citrus Leafminer

    Bookmark   April 24, 2012 at 2:26PM
Thank you for reporting this comment. Undo

hoosierquilt: Thank you so much for the response. I think you nailed it. I didn't think it was a parasite because I could never see any bugs, but as the article states, they are rarely seen. I'll gladly return the $15 bottle of fungicide and let nature take it's course. Thank God for forums like this!

Ha, now I just have to figure out what this massive hornet is that I caught (and killed) in my garden last night. I thought it was a monster bumble bee by the markings, but then I noticed it had a dead honeybee in it's mouth. That will not fly in my yard (no pun intended). It was funny how upset I felt that it had killed one of my girls...
Thanks again for your help. God bless!

    Bookmark   April 24, 2012 at 3:08PM
Thank you for reporting this comment. Undo
hoosierquilt USDA 10A Sunset 23 Vista CA

Yup. Fungicide's are nasty products. I try to not use them if at all possible or use more organic alternatives (but for some folks, it's difficult not to.) I think there's a great bug web site, that can help you to ID your wasp.

Patty S.

    Bookmark   April 24, 2012 at 4:54PM
Sign Up to comment
More Discussions
Broken Satsuma and Kumquat trees
Hello all. Last May, I planted satsuma and kumquat...
Strange happenings with lemon tree
Hi, This is my first post, upon finding your site. I...
Help with citrus scale
Hello all, my satsuma mandarin is dropping leaves....
Bugs 16
Bugs 15 is getting to big so starting this one. Trace...
tcamp30144(7B N.ATLANTA)
My lemon tree needs help!
Hello, I recently got a new house with some citrus...
Roderick Agius
© 2015 Houzz Inc. Houzz® The new way to design your home™