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Gooey white and black on citrus

Posted by DoobieSnax 9 (SETX) (My Page) on
Sun, Aug 28, 11 at 23:18

I work in a nursery and we have been haveing a problem on our citrus. we have tried everything. Its white and gooey on the bottom of the leaves. somtimes has black moldy looking stuff with it but mostly the white....we have treated for bugs fungus and mites still it pops back up...anyone wanna guess? im getting pictures next day i work


Follow-Up Postings:

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RE: Gooey white and black on citrus

The white, "gooey" stuff is an insect problem... probably scale; the black mold is feeding on the white gooey stuff.

Treat with horticultural oil, with a little copper; or depending on how many plants you have, just wash them really good, or spray with Safer soap and clean the leaves by hand..

On my Meyer farm I apply Bayer Silvacur once a year at the start of the rainy season...kills any fungus on the leaves, and also enters the plant as systemic... then all you have to worry about are insects.


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RE: Gooey white and black on citrus

Sounds like Greasy Spot. You might want to make sure you spend some time on your Texas Cooperative Extension web site. Wealth of info there for commercial growers.

Patty S.

Here is a link that might be useful: Texas Citrus - Texas Citrus Diseases


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RE: Gooey white and black on citrus

well we have tried washing the leaves along with oil and malithion nothing worked im taking pics today....BTW we have close to 150 citrus trees.....''/


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RE: Gooey white and black on citrus

Doobie, if this is Greasy Spot, malathion will not control it, as it is a fugus, and not an insect. The treatment for Greasy Spot is spraying in the summer with neutral copper or oil. But at this point, I would contact your local county extension office immediately, to get a diagnosis. With this many trees at risk, you need to call in the big guns.

Patty S.


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RE: Gooey white and black on citrus

http://i20.photobucket.com/albums/b235/Neelahn/DSC00491.jpg
http://i20.photobucket.com/albums/b235/Neelahn/DSC00486.jpg
http://i20.photobucket.com/albums/b235/Neelahn/DSC00485.jpg
http://i20.photobucket.com/albums/b235/Neelahn/DSC00484.jpg

and just for fun here is a pretty bowl
http://i20.photobucket.com/albums/b235/Neelahn/DSC00488.jpg


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RE: Gooey white and black on citrus

At first I thought perhaps Woolly whitefly. After seeing this image, though, I wonder if it's a scale that puts out waxy filaments. http://i20.photobucket.com/albums/b235/Neelahn/DSC00484.jpg Don't know what's busy in TX.

As has been suggested, the black stuff is evidence of sooty mold (not a disease) which feeds on the sticky honeydew excreted by the insects.

Here is a link that might be useful: insects & sooty mold


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RE: Gooey white and black on citrus

im sry your link is wrong XD that's my picture ....but anyways i was looking very close at one tree and i couldn't see any bug so they have to be very tiny BTW we are trying Oilspray again


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RE: Gooey white and black on citrus

Let us know what the final diagnosis is, Doobie. And see if your local county extension agent can come take a look for you, and give you a correct diagnosis. This might save you some time, work and money by selecting the most correct treatment. I know this must be a bit nerve-wracking with all those trees at stake!

Patty S.


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RE: Gooey white and black on citrus

After seeing the fotos I am more convinced that my first suggestion was correct... a scale problem with the black mold feeding on the sticky excretions of the scale.
If you are looking for a flying/walking insect, you won't find it... the white stuff is the insect/scale; it moves, but VERY slowly. I'll attach a link to learn more about scale on citrus; it is from West Australia, but valid for US.
Also, don't expect the copper/oil spray to make the problem disappear; because the scale sticks to the plant, when it is dead, it will still be stuck there...it has to be physically removed, after maybe a week... by washing or removing by hand. BTW... it is a good idea to give citrus a regular washing to help prevent dust, mites, spiders, etc

Here is a link that might be useful: Scale on citrus


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RE: Gooey white and black on citrus

Yes, I know that's your picture. I linked to it so that everyone could see what I was talking about.

PLEASE stop throwing pesticides and whatever else at it until you get a firm diagnosis. To do so, take a sample, secured in a clear container, to you county's Extension Service office. Many of the offices also accept clear digital images.

Locate your office with this clickable USDA map
http://www.csrees.usda.gov/Extension/

Here is a link that might be useful: USDA map to locate Extension Service offices


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RE: Gooey white and black on citrus

ok we treated with oilspray again with a bit of Malithion in it and that seems to be getting it....ive been looking more on the net and i think it might have been aphids but im not sure i just hope this gets it...Jean i know its not the best thing to do (treating b4 we know what it is) but when you have sick trees you cant sell you have to do something...

ty everyone for your input


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RE: Gooey white and black on citrus

Doobie, I agree with Jean, here. Besides throwing a bunch of pesticides on your trees, you may simply be wasting monies. I would get a diagnosis as both Jean and I have suggested previously from your local county extension office, so you know exactly what you're dealing with, and can then treat your trees accordingly, instead of just guessing. And possibly spending monies you don't need to. Plus, not so sure customers would be thrilled to know their citrus trees they plan on purchasing in order to eat fruit have been drenched with malathion. I know as a customer, I make sure I purchase trees from growers that do not use these sorts of pesticides. Just a thought for you to consider, for your customers.

Patty S.


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RE: Gooey white and black on citrus

If you're a seller, you MUST work with an Extension Agent, NOT a public forum of home gardeners, even though many of us are quite knowledgeable.

Be a responsible seller. Stop guessing!


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RE: Gooey white and black on citrus

I add my support to working with pros.. find a good entemologist for sure... Imagine having these kind of problems in a NURSERY!! In my nurseries (2) I review every plant every day; and stop whatever is bothering the plants BEFORE it spreads. Often just a simple washing solves whatever comes along...LONG before chemicals become necessary. I don't even have problems like this in the field, much less in the nursery.


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RE: Gooey white and black on citrus

Doobie, here is an article that will knock the sock off your feet!

I hope this does not prove to be true in your case. Watch for them spider mites now since any natural predators will have no hold now.

MIke

http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7405.html

Here is a link that might be useful: Spider mites form chemical sprays


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RE: Gooey white and black on citrus

Doobie, you can't sell your trees (you're selling trees and not oranges, right?) UNTIL you find out what's wrong. Doing so could really get you into trouble, big time. I'm more than a little surprised that your country Extension people haven't been called out there the minute you observed something. That's there job.

Please don't forget to come back and share with us what you learn. I think that we would all be interested. I've never seen anything 'quite' like this. Close but not exact.


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